Summary of Significant Accounting Policies (Policies)	12 Months Ended
Summary of Significant Accounting Policies (Policies)	Dec. 31, 2018
Accounting Policies [Abstract]
Allowance for Loan and Lease Losses	Allowance for Loan and Lease Losses TCF's reserving methodology used to determine the appropriate level of the allowance for loan and lease losses contains critical accounting estimates. The allowance for loan and lease losses is maintained at a level believed to be appropriate to provide for probable loan and lease losses incurred in the portfolio as of the balance sheet date, including known or anticipated problem loans and leases, as well as for loans and leases which are not currently known to require specific allowances. Loans classified as troubled debt restructuring ("TDR") loans are considered impaired loans, along with non-accrual commercial, equipment finance and inventory finance loans. TCF individually evaluates impairment on all impaired loans and all non-accrual leases and other consumer real estate, commercial and auto finance loans specifically identified for evaluation. All other loans and leases are evaluated collectively for impairment. Loan impairment on consumer real estate TDR loans is a key component of the allowance for loan and lease losses. Impairment is generally based on the present value of the expected future cash flows discounted at the loan's initial effective interest rate, unless the loans are collateral dependent, in which case loan impairment is based on the fair value of the collateral less estimated selling costs. Impairment on commercial loans, inventory finance loans and leasing and equipment finance loans and leases is generally based on the present value of the expected future cash flows discounted at the initial effective interest rate of the loan or lease, unless the loan or lease is collateral dependent, in which case impairment is based on the fair value of collateral less estimated selling costs; however, if payment or satisfaction of the loan or lease is dependent on the operation, rather than the sale of the collateral, the impairment does not include estimated selling costs. Impairment on auto finance loans is generally based on the fair value of collateral less estimated selling costs. The impairment for all other loans and leases is evaluated collectively by various characteristics. The collective evaluation of incurred losses in these portfolios is based on their historical loss rates multiplied by the respective loss emergence period. Factors utilized in the determination of the amount of the allowance include historical trends in loss rates, a portfolio's overall risk characteristics, changes in its character or size, risk rating migration, delinquencies, collateral values, economic outlook and prevailing economic conditions. The various factors used in the methodologies are reviewed on a periodic basis. Loans and leases are charged off to the extent they are deemed to be uncollectible. Charge-offs are utilized in the historical data in calculating the allowance for loan and lease losses. Consumer real estate loans are charged off to the estimated fair value of the underlying collateral, less estimated selling costs, no later than 150 days past due. Additional review of the fair value, less estimated costs to sell, compared with the recorded value occurs upon foreclosure and additional charge-offs are recorded if necessary. Commercial loans, leasing and equipment finance loans and leases and inventory finance loans that are considered collateral dependent are charged off to estimated fair value, less estimated selling costs when it becomes probable, based on current information and events, that all principal and interest amounts will not be collectible in accordance with their contractual terms. Auto finance loans will be charged off in full no later than 120 days past due, unless repossession is reasonably assured and in process, in which case the loan would be charged off to the fair value of the collateral, less estimated selling costs. Consumer real estate and auto finance loans in bankruptcy status may be charged down to the fair value of the collateral, less estimated selling costs, within 60 days past due based on specific criteria. Deposit account overdrafts are reported in other loans. Net losses on uncollectible overdrafts are reported as net charge-offs in the allowance for loan and lease losses within 60 days from the date of overdraft. Loans that are not collateral dependent are charged off when deemed uncollectible based on specific facts and circumstances. The amount of the allowance for loan and lease losses significantly depends on management's estimates of variables affecting valuation, appraisals of collateral, evaluations of performance and status and the amounts and timing of future cash flows expected to be received. Such estimates, appraisals, evaluations and cash flows may be subject to frequent adjustments due to changing economic prospects of borrowers, lessees or properties. These estimates are reviewed quarterly and adjustments, if necessary, are recorded in the provision for credit losses in the periods in which they become known. See Note 7. Allowance for Loan and Lease Losses and Credit Quality Information for further information on the allowance for loan and lease losses.
Debt Securities Held to Maturity and Available for Sale	Debt Securities Held to Maturity Debt securities held to maturity are carried at cost and adjusted for amortization of premiums or accretion of discounts using a level yield method; however, transfers of debt securities available for sale to debt securities held to maturity are made at fair value at the date of transfer. The unrealized holding gain or loss at the date of each transfer is retained in accumulated other comprehensive income (loss) and in the carrying value of the held to maturity debt security. Such amounts are then amortized over the remaining life of the transferred debt security as an adjustment of the yield on those debt securities. TCF evaluates debt securities held to maturity for other than temporary impairment on a quarterly basis. Declines in value considered other than temporary, if any, would be recorded in non-interest income within gains (losses) on debt securities, net. See Note 5. Debt Securities Available for Sale and Debt Securities Held to Maturity for further information on debt securities held to maturity. Debt Securities Available for Sale Debt securities available for sale are carried at fair value with the unrealized gains or losses net of related deferred income taxes reported within accumulated other comprehensive income (loss). The cost of debt securities sold is determined on a specific identification basis and gains or losses on sales of debt securities available for sale are recognized on trade dates. Discounts and premiums on debt securities available for sale are amortized using a level yield method over the expected life of the debt security, or to the earliest call date for premiums on debt securities with call features. TCF evaluates debt securities available for sale for other than temporary impairment on a quarterly basis. Declines in value considered other than temporary, if any, would be recorded in non-interest income within gains (losses) on debt securities, net. See Note 5. Debt Securities Available for Sale and Debt Securities Held to Maturity for further information on debt securities available for sale.
Loans and Leases Held for Sale	Loans and Leases Held for Sale Loans and leases designated as held for sale are generally carried at the lower of cost or fair value. Any amount by which cost exceeds fair value is initially recorded as a valuation allowance and subsequently recorded in the gain or loss on sale when sold. Certain other loans held for sale are recorded at fair value under the elected fair value option. From time to time, management identifies and designates, primarily consumer real estate, loans held in the loan portfolios for sale. These loans are transferred to loans and leases held for sale at the lower of cost or fair value at the time of transfer net of any associated allowance for loan and lease losses.
Loans and Leases	Loans and Leases Loans and leases are reported at historical cost including net direct fees and costs associated with originating and acquiring loans and leases. The net direct fees and costs for sales-type leases are offset against revenues recorded at the commencement of sales-type leases. Discounts and premiums on acquired loans, net direct fees and costs, unearned discounts and finance charges, and unearned lease income are amortized to interest income using methods that approximate a level yield over the estimated remaining lives of the loans and leases. Net direct fees and costs on all lines of credit are amortized on a straight line basis over the contractual life of the line of credit and adjusted for payoffs. Net deferred fees and costs on consumer real estate lines of credit are amortized to fees and service charges. See Note 6. Loans and Leases for further information on loans and leases. TCF acquires loans and leases through business combinations and purchases of loan and lease portfolios. These loans and leases are recorded at fair value at the acquisition date and the fair value discount or premium is recognized as an adjustment to yield over the remaining life of each loan or lease. Credit discounts are included in the determination of fair value; therefore, an allowance for loan and lease losses is not recorded at the acquisition date. Purchased loans are evaluated at the acquisition date and classified as purchased loans or purchased credit impaired ("PCI") loans. Loans are considered PCI loans if it is probable at the acquisition date that all contractually required payments will not be collected. Upon acquisition, the acquired PCI loans are recorded at fair value without a corresponding allowance for loan losses as the non-accretable discount is adequate to absorb expected remaining credit losses. The excess of expected cash flows to be collected over the initial fair value of the acquired portfolios is referred to as the accretable yield and is accreted into interest income over the estimated life of the acquired portfolios using the effective yield method. The accretable yield is affected by changes in interest rate indices for variable-rate acquired portfolios, changes in prepayment assumptions and changes in the expected principal and interest payments over the estimated life of the loan. These acquired loans are classified as accruing and interest income continues to be recognized unless expected credit losses exceed the non-accretable discount. If subsequent to acquisition there is credit deterioration in excess of the acquisition date credit discount for PCI loans or purchased loans and leases, an additional allowance for loan and lease losses is established.
Non-accrual Loans and Leases	Non-accrual Loans and Leases Loans and leases are generally placed on non-accrual status when the collection of interest or principal is 90 days or more past due, unless, in the case of commercial loans, they are well secured and in the process of collection. Delinquent consumer real estate junior lien loans are placed on non-accrual status when there is evidence that the related third-party first lien mortgage may be 90 days or more past due, or foreclosure, charge-off or collection action has been initiated. TDR loans are placed on non-accrual status prior to the past due thresholds outlined above if repayment under the modified terms is not likely after performing a well-documented credit analysis. Loans on non-accrual status are generally reported as non-accrual loans until there is sustained repayment performance for six consecutive months, with the exception of loans not reaffirmed upon discharge under Chapter 7 bankruptcy, which remain on non-accrual status until a well-documented credit analysis indicates full repayment of the remaining pre-discharged contractual principal and interest is likely. Income on these loans is recognized on a cash basis when there is sustained repayment performance for nine or 12 consecutive months based on the credit evaluation and the loan is not more than 60 days delinquent. Generally, when a loan or lease is placed on non-accrual status, uncollected interest accrued in prior years is charged off against the allowance for loan and lease losses and interest accrued in the current year is reversed against interest income. For non-accrual leases that have been discounted with third-party financial institutions on a non-recourse basis, the related liability is also placed on non-accrual status. Interest payments received on loans and leases in non-accrual status are generally applied to principal unless the remaining principal balance has been determined to be fully collectible, in which case interest income is recognized on a cash basis. See Note 7. Allowance for Loan and Lease Losses and Credit Quality Information for further information on non-accrual loans and leases.
Lease Financing	Lease Financing TCF provides various types of commercial lease financing that are classified for accounting purposes as direct financing, sales-type or operating leases. Leases that transfer substantially all of the benefits and risks of ownership to the lessee are classified as direct financing or sales-type leases and are included in loans and leases. Direct financing and sales-type leases are carried at the combined present value of future minimum lease payments and lease residual values. The determination of lease classification requires various judgments and estimates by management including the fair value of the equipment at lease inception, useful life of the equipment under lease, estimate of the lease residual value and collectability of minimum lease payments. Sales-type leases generate dealer profit, which is recognized at lease inception by recording lease revenue net of lease cost. Lease revenue consists of the present value of the future minimum lease payments. Lease cost consists of the leased equipment's book value, less the present value of its residual. Interest income on direct financing and sales-type leases is recognized using methods that approximate a level yield over the fixed, non-cancelable term of the lease. TCF receives pro rata rent payments for the interim period until the lease contract commences and the fixed, non-cancelable lease term begins. TCF recognizes these interim payments in the month they are earned and records the income in interest income. Management has policies and procedures in place for the determination of lease classification and review of the related judgments and estimates for all lease financings. Some lease financings include a residual value component, which represents the estimated fair value of the leased equipment at the expiration of the initial term of the transaction. The estimation of residual values involves judgment regarding product and technology changes, customer behavior, shifts in supply and demand and other economic assumptions. TCF reviews residual assumptions in the portfolio at least annually and records impairment, if necessary, which is charged to non-interest expense in the periods in which it becomes known. TCF may sell minimum lease payments primarily as a credit risk reduction tool to third-party financial institutions at fixed rates on a non-recourse basis with its underlying equipment as collateral. For those transactions that achieve sale treatment, the related lease cash flow stream and the non-recourse financing are derecognized. For those transactions that do not achieve sale treatment, the underlying lease remains on TCF's Consolidated Statements of Financial Condition and non-recourse debt is recorded in the amount of the proceeds received. TCF retains servicing of these leases and bills, collects and remits funds to the third-party financial institution. Upon default by the lessee, the third-party financial institutions may take control of the underlying collateral which TCF would otherwise retain as residual value. Leases that do not transfer substantially all benefits and risks of ownership to the lessee are classified as operating leases. Such leased equipment and related initial direct costs are included in other assets and depreciated on a straight-line basis over the term of the lease to its estimated salvage value. Depreciation expense on the leased equipment is recorded in non-interest expense. Operating lease rental income is recognized when it is due and is recorded as a component of leasing and equipment finance non-interest income. An allowance for lease losses is not provided on operating leases.
Premises and Equipment	Premises and Equipment Premises and equipment, including leasehold improvements, are carried at cost and are depreciated or amortized on a straight-line basis over the estimated useful lives of owned assets, over the lease term for capitalized leases and over the estimated useful life of the related asset or the lease term, whichever is shorter, for leasehold improvements. Maintenance and repairs are charged to expense as incurred. Rent expense for leased land with facilities is recognized in occupancy and equipment expense. Rent expense for leases with free rent periods or scheduled rent increases is recognized on a straight-line basis over the lease term. See Note 8. Premises and Equipment, Net for further information on premises and equipment.
Other Real Estate Owned and Repossessed and Returned Assets	Other Real Estate Owned and Repossessed and Returned Assets Assets acquired through foreclosure, repossession or returned to TCF are initially recorded at the lower of the loan or lease carrying amount or fair value of the collateral less estimated selling costs at the time of transfer to real estate owned or repossessed and returned assets. The fair value of other real estate owned is based on independent appraisals, real estate brokers' price opinions or automated valuation methods, less estimated selling costs. The fair value of repossessed and returned assets is based on available pricing guides, auction results or price opinions, less estimated selling costs. Any carrying amount in excess of the fair value less estimated selling costs is charged off to the allowance for loan and lease losses upon transfer. Subsequently, if the fair value of an asset, less the estimated costs to sell, declines to less than the carrying amount of the asset, the shortfall is recognized in the period in which it becomes known and is included in foreclosed real estate and repossessed assets, net expense. Operating expenses of properties and recoveries on sales of other real estate owned are also recorded in non-interest expense within foreclosed real estate and repossessed assets, net expense. Operating revenue from foreclosed property is included in other non-interest income. See Note 7. Allowance for Loan and Lease Losses and Credit Quality Information for further information on other real estate owned and repossessed and returned assets.
Investments in Affordable Housing Limited Liability Entities	Investments in Affordable Housing Limited Liability Entities TCF has investments in affordable housing limited liability entities that either operate qualified affordable housing projects or invest in other limited liability entities formed to operate affordable housing projects, which TCF generally accounts for under the proportional amortization method. However, depending on circumstances, the effective yield, equity or cost methods may be utilized. The amount of the investments, along with any unfunded equity contributions that are unconditional and legally binding, are recorded in other assets. A liability for the unfunded equity contributions is recorded at fair value in accrued expenses and other liabilities. The tax credits and amortization of the investments are recorded as a component of income tax expense (benefit). See Note 10. Investments in Affordable Housing Limited Liability Entities for further information on investments in affordable housing limited liability entities.
Interest-only Strips	Interest-only Strips TCF sells loans with or without interest-only strips to third party financial institutions. For those transactions that achieve sale treatment, the underlying loans are removed from TCF's Consolidated Statements of Financial Condition. The Company may receive as part of the sale consideration an interest in the future cash flows of borrower loan payments, known as an interest-only strip. The interest-only strip is recorded at fair value in other assets with the unrealized gains or losses net of deferred income taxes reported within accumulated other comprehensive income (loss). The fair value of the interest-only strip represents the present value of future cash flows expected to be received by TCF. After initial recording of the interest-only strip, the accretable yield is measured as the difference between the initial investment, or fair value, and the cash flows expected to be collected. The accretable yield is amortized into interest income over the life of the interest-only strip using the effective yield method. The expected cash flows are evaluated quarterly to determine if they have changed from previous projections. Declines in the value of interest-only strips that are considered other than temporary are recorded in other non-interest expense. See Note 6. Loans and Leases for further information on interest-only strips.
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets All assets and liabilities acquired in purchase acquisitions, including other intangibles, are initially recorded at fair value. Goodwill is recorded when the purchase price of an acquisition is greater than the fair value of net assets, including identifiable intangible assets. Goodwill is not amortized, but assessed for impairment on at least an annual basis at the reporting unit level. Interim impairment analysis may be required if events occur or circumstances change that would more likely than not reduce a reporting unit's fair value below its carrying amount. Other intangible assets are amortized on a straight-line basis or accelerated method over their estimated useful lives and are subject to impairment if events or circumstances indicate a possible inability to realize their carrying amounts. When testing for goodwill impairment, TCF has the option to perform a qualitative assessment of goodwill. TCF may also elect to perform a quantitative test without first performing a qualitative analysis. If the qualitative assessment is performed and TCF concludes it is more likely than not that a reporting unit's fair value is less than its carrying amount, a quantitative analysis is performed. Quantitative valuation methodologies primarily include a discounted cash flow analysis in determining the fair value of reporting units. If the fair value is less than the carrying amount, additional analysis is required to measure the amount of impairment. Impairment losses, if any, are recorded as a charge to non-interest expense and an adjustment to the carrying value of goodwill. Other intangible assets are reviewed for impairment whenever events or changes in circumstances indicate their carrying amount may not be recoverable. Impairment is indicated if the sum of the undiscounted estimated future net cash flows is less than the carrying value of the intangible asset. Impairment losses, if any, permanently reduce the carrying value of the other intangible assets. See Note 9. Goodwill and Other Intangible Assets for further information on goodwill and other intangible assets.
Derivatives	Derivative Instruments All derivative instruments are recognized at fair value within other assets or accrued expenses and other liabilities. The Company's derivative instruments may be subject to master netting arrangements and collateral arrangements and qualify for offset in the Consolidated Statements of Financial Condition. A master netting arrangement with a counterparty creates a right of offset for amounts due to and from that same counterparty that is enforceable in the event of a default or bankruptcy. The Company's policy is to recognize amounts subject to master netting arrangements and collateral arrangements on a net basis in the Consolidated Statements of Financial Condition. The value of derivative instruments will vary over their contractual terms as the related underlying rates fluctuate. The accounting for changes in the fair value of a derivative instrument depends on whether or not the contract has been designated and qualifies as a hedge. To qualify as a hedge, a contract must be highly effective at reducing the risk associated with the exposure being hedged. In addition, for a contract to be designated as a hedge, the risk management objective and strategy must be documented at inception. Hedge documentation must also identify the hedging instrument, the asset or liability and type of risk to be hedged and how the effectiveness of the contract is assessed prospectively and retrospectively. To assess effectiveness, TCF uses statistical methods such as regression analysis. A contract that has been, and is expected to continue to be effective at offsetting changes in fair values or the net investment, must be assessed and documented at least quarterly. If it is determined that a contract is not highly effective at hedging the designated exposure, hedge accounting is discontinued. Upon origination of a derivative instrument, the contract is designated either as a hedge of the exposure to changes in the fair value of an asset or liability due to changes in market risk ("fair value hedge"), a hedge of the volatility of an investment in foreign operations driven by changes in foreign currency exchange rates ("net investment hedge") or is not designated as a hedge. Fair Value Hedges TCF Bank entered into an interest rate swap agreement related to its contemporaneously issued subordinated debt, which settles through a central clearing house. The swap was designated as a fair value hedge and effectively converts the fixed interest rate to a floating rate based on the three-month London InterBank Offered Rate ("LIBOR") plus a fixed number of basis points on the $150.0 million notional amount through February 27, 2025, the maturity date of the subordinated debt. The interest rate swap substantially offsets the change in fair value of the hedged underlying subordinated debt that is attributable to the changes in market risk. The gains and losses related to changes in the fair value of the interest rate swap, as well as the offsetting changes in fair value of the hedged debt, are recorded in interest expense - borrowings effective January 1, 2018 and were previously recorded in other non-interest income. Net Investment Hedges Forward foreign exchange contracts, which generally settle within 34 days, are used to manage the foreign exchange risk associated with the Company's net investment in TCF Commercial Finance Canada, Inc. ("TCFCFC"), a wholly-owned indirect Canadian subsidiary of TCF Bank. Changes in net investment hedges recorded within other comprehensive income (loss) are subsequently reclassified to non-interest expense during the period in which the foreign investment is substantially liquidated or when other elements of the currency translation adjustment are reclassified to income. Derivatives Not Designated as Hedges TCF executes interest rate contracts with commercial banking customers to facilitate their respective risk management strategies. Those interest rate contracts are simultaneously hedged with offsetting interest rate contracts that TCF executes with a third party and generally settles through a central clearing house, minimizing TCF's net risk exposure. As the interest rate contracts do not meet hedge accounting requirements, changes in the fair value of both the customer contracts and the offsetting contracts are recorded in other non-interest income. These contracts have original fixed maturity dates ranging from three to 11 years. Certain of TCF's forward foreign exchange contracts are not designated as hedges and are generally settled within 34 days. Changes in the fair value of these forward foreign exchange contracts are recorded in other non-interest expense. TCF enters into interest rate lock commitments in conjunction with the sale of certain consumer real estate loans. These interest rate lock commitments are agreements to extend credit under certain specified terms and conditions at fixed rates with original lock expirations generally within three months. They are not designated as hedges and accordingly, changes in the valuation of these commitments are recorded in gains on sales of loans, net. During the second quarter of 2012, TCF sold its Visa^® Class B stock. In conjunction with the sale, TCF and the purchaser entered into a derivative transaction whereby TCF may receive or be required to make cash payments whenever the conversion ratio of the Visa Class B stock into Visa Class A stock is adjusted. The fair value of this derivative has been determined using estimated future cash flows using probability weighted scenarios for multiple estimates of Visa's aggregate exposure to covered litigation matters, which include consideration of amounts funded by Visa into its escrow account for the covered litigation matters. Changes, if any, in the valuation of this swap agreement, which has no determinable maturity date, are recorded in other non-interest expense. See Note 20. Derivative Instruments for further information on derivative instruments.
Income Taxes	Income Taxes Income taxes are accounted for using the asset and liability method. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis carrying amounts. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recorded in income tax expense (benefit) in the period in which the enactment date occurs. If current period income tax rates change, the impact on the annual effective income tax rate is applied year to date in the period of enactment. The determination of current and deferred income taxes is based on analyses of many factors, including interpretation of income tax laws, the evaluation of uncertain tax positions, differences between the tax and financial reporting bases of assets and liabilities (temporary differences), estimates of amounts due or owed, the timing of reversals of temporary differences and current financial accounting standards. Additionally, there can be no assurance that estimates and interpretations used in determining income tax assets or liabilities will not be challenged by taxing authorities. Actual results could differ significantly from the estimates and tax law interpretations used in determining the current and deferred income tax assets and liabilities. In the preparation of income tax returns, tax positions are taken based on interpretation of income tax laws for which the outcome is uncertain. At each balance sheet date, management reviews and evaluates the status of uncertain tax positions and makes estimates of amounts ultimately due or owed. The benefits of tax positions are recorded in income tax expense (benefit) net of the estimates of ultimate amounts due or owed, including any applicable interest and penalties. Changes in the estimated amounts due or owed may result from closing of the statute of limitations on tax returns, new legislation, clarification of existing legislation through government pronouncements, judicial action and through the examination process. TCF's policy is to record interest and penalties, if any, related to unrecognized tax benefits in income tax expense (benefit). See Note 14. Income Taxes for further information on income taxes.
Stock-based Compensation	Stock-based Compensation The fair value of restricted stock, stock options and restricted stock units is determined on the date of grant and amortized to compensation and employee benefits expense, with a corresponding increase to additional paid-in capital, over the longer of the service period or performance period, but in no event beyond an employee's retirement date or date of employment termination. For performance-based restricted stock or stock units, TCF estimates the degree to which performance conditions will be met to determine the number of shares or units that will vest and the related expense. Compensation and employee benefits expense is adjusted in the period such estimates change. Non-forfeitable dividends, if any, paid on shares of restricted stock are recorded to retained earnings for shares that are expected to vest and to compensation and employee benefits expense for shares that are not expected to vest. Income tax benefits (detriments) related to stock compensation, where the fair value on vesting or exercise of the award is greater than (less than) the grant date value less any proceeds on exercise, are recognized in income tax expense (benefit). See Note 17. Stock Compensation for further information on stock-based compensation.
Earnings Per Common Share	Earnings Per Common Share TCF's restricted stock awards that pay non-forfeitable common stock dividends meet the criteria of a participating security. Accordingly, earnings per share is calculated using the two-class method under which earnings are allocated to both common shares and participating securities. All shares of restricted stock are deducted from weighted-average shares outstanding for the computation of basic earnings per common share. Shares of performance-based restricted stock and restricted stock units are included in the calculation of diluted earnings per common share using the treasury stock method at the beginning of the quarter in which the performance goals have been achieved. All other shares of restricted stock, which vest over specified time periods, stock options and warrants are included in the calculation of diluted earnings per common share using the treasury stock method. See Note 22. Earnings Per Common Share for further information on earnings per share.
New Accounting Pronouncements Recently Adopted or Issued	Recently Adopted Accounting Pronouncements Effective January 1, 2018, the Company adopted Accounting Standards Update ("ASU") No. 2018-14: Compensation - Retirement Benefits - Defined Benefit Plans - General (Subtopic 715-20): Disclosure Framework - Changes to the Disclosure Requirements for Defined Benefit Plans, which eliminates, adds and modifies certain annual disclosure requirements for employers that sponsor defined benefit pension and/or other postretirement benefit plans. The adoption of this ASU was on a retrospective basis. The adoption of this guidance did not have a material impact on our consolidated financial statements. Effective January 1, 2018, the Company adopted ASU No. 2017-12: Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities, which expands hedge accounting for nonfinancial and financial risk components and amends measurement methodologies to more closely align hedge accounting with a company’s risk management activities. The ASU decreases the complexity of preparing and understanding hedge results through measurement and reporting of hedge ineffectiveness. In addition, disclosures have been enhanced and the presentation of hedged results changed to align the effects of the hedging instrument and the hedged item. The adoption of this ASU was on a modified retrospective basis and resulted in the Company recording a cumulative effect reduction to the opening balance of retained earnings of $116 thousand. Effective January 1, 2018, the Company adopted ASU No. 2017-09: Compensation - Stock Compensation (Topic 718): Scope of Modification Accounting, which provides guidance about which changes to the terms and conditions of a share-based payment award requires an entity to apply modification accounting in Topic 718. The adoption of this ASU was on a prospective basis and will be applicable to an award modified on or after January 1, 2018. The adoption of this guidance did not have a material impact on our consolidated financial statements. Effective January 1, 2018, the Company adopted ASU No. 2017-07: Compensation - Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost, which changes how employers that sponsor defined benefit pension and/or other postretirement benefit plans present the net periodic benefit cost in the income statement. Under the new guidance, employers present the service cost component of the net periodic benefit cost in the same income statement line item as other employee compensation costs arising from services rendered during the period. Only the service cost component is eligible for capitalization in assets. The other components of net periodic benefit cost are presented separately from the line item that includes service cost and outside of any subtotal of operating income. In addition, disclosure of the line items used to present the other components of net periodic benefit cost is required if the components are not presented separately in the income statement. The adoption of this ASU was on a modified retrospective basis. The adoption of this guidance did not have a material impact on our consolidated financial statements. Effective January 1, 2018, the Company adopted ASU No. 2017-05: Other Income - Gains and Losses from the Derecognition of Nonfinancial Assets (Subtopic 610-20): Clarifying the Scope of Asset Derecognition Guidance and Accounting for Partial Sales of Nonfinancial Assets, which provides guidance for recognizing gains and losses from the transfer of nonfinancial assets in contracts with non-customers. The ASU also clarifies that Accounting Standards Codification 610-20 applies to the derecognition of nonfinancial assets and in substance nonfinancial assets unless other specific guidance applies or the sale is to a customer. The guidance does not apply to the derecognition of businesses, nonprofit activities, financial assets, including equity method investments, or to revenue contracts with customers. The adoption of this ASU was on a modified retrospective basis. The adoption of this guidance did not have a material impact on our consolidated financial statements. Effective January 1, 2018, the Company adopted ASU No. 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business, which clarifies the definition of a business with the objective of adding guidance to assist companies with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The ASU provides a more robust framework to use in determining when a set of assets and activities is a business. The adoption of this ASU was on a prospective basis. TCF will evaluate future transactions to determine if they should be accounted for as acquisitions (or disposals) of assets or businesses. Effective January 1, 2018, the Company adopted ASU No. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash, which requires entities to show changes in the total of cash, cash equivalents, restricted cash and restricted cash equivalents in the statement of cash flows. As a result, entities no longer present transfers between cash and cash equivalents, restricted cash and restricted cash equivalents in the statement of cash flows. The adoption of this ASU was on a retrospective basis. The adoption of this guidance did not have an impact on our consolidated financial statements. Effective January 1, 2018, the Company adopted ASU No. 2016-17, Consolidation (Topic 810): Interests Held through Related Parties That Are under Common Control, which changes the way in which a single decision maker considers indirect interests when performing the primary beneficiary analysis under the variable interest model. Under the amended guidance, indirect interests held by a related party would be considered on a proportional basis. The adoption of this ASU was on a retrospective basis. The adoption of this guidance did not have a material impact on our consolidated financial statements. Effective January 1, 2018, the Company adopted ASU No. 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory, which requires the income tax effects of intercompany sales and transfers of assets, other than inventory, to be recognized in the period the transaction occurs. The adoption of this ASU was on a modified retrospective basis. The adoption of this guidance did not have a material impact on our consolidated financial statements. Effective January 1, 2018, the Company adopted ASU No. 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments, which addresses eight specific cash flow issues with the objective of reducing the existing diversity in practice in how certain types of cash receipts and cash payments are presented in the statement of cash flows. The adoption of this ASU was on a retrospective basis. The adoption of this guidance did not have a material impact on our consolidated financial statements. Effective January 1, 2018, the Company adopted ASU No. 2016-04, Liabilities - Extinguishments of Liabilities (Subtopic 405-20): Recognition of Breakage for Certain Prepaid Stored-Value Products, which requires issuers of prepaid stored-value products redeemable for goods, services or cash at third-party merchants to derecognize liabilities related to those products for breakage. The adoption of this ASU was on a modified retrospective basis. The adoption of this guidance did not have a material impact on our consolidated financial statements. Effective January 1, 2018, the Company adopted ASU No. 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities and ASU No. 2018-03, Technical Corrections and Improvements to Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities, which amend the classification and measurement of investments in equity securities, simplify the impairment analysis of equity investments without readily determinable fair values, require separate presentation of certain fair value changes for financial liabilities measured at fair value and eliminate certain disclosure requirements associated with the fair value of financial instruments. The adoption of these ASUs was on a prospective basis. The adoption of this guidance did not have a material impact on our consolidated financial statements. Effective January 1, 2018, the Company adopted the following ASUs using the modified retrospective method with no cumulative-effect adjustment to opening retained earnings: ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606); ASU No. 2015-14, Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date; ASU No. 2016-08, Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations (Reporting Revenue Gross versus Net); ASU No. 2016-10, Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing; ASU No. 2016-12, Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients; ASU No. 2016-20, Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers; ASU No. 2017-13, Revenue Recognition (Topic 605), Revenue from Contracts with Customers (Topic 606), Leases (Topic 840), and Leases (Topic 842): Amendments to SEC Paragraphs and ASU No. 2017-14, Income Statement - Reporting Comprehensive Income (Topic 220), Revenue Recognition (Topic 605), and Revenue from Contracts with Customers (Topic 606). TCF derives a majority of its revenue from loans and leases, as well as any related servicing fee revenue, which are not within the scope of these ASUs. These ASUs are applicable to most of the fees and service charges, card and ATM revenue earned by TCF, as well as the gains on sales of certain non-financial assets. However, the recognition of these revenue streams does not change in a significant manner as a result of the adoption of these ASUs. The majority of this revenue is both charged to the customer and earned either at a point in time or on a transactional basis. As a result, the revenue expected to be recognized in any future year related to remaining performance obligations, contracts where revenue is recognized when invoiced and contracts with variable consideration related to undelivered performance obligations are not material. In addition, receivables related to fees and service charges and the related bad debt expense are not material. There are no material contract assets, contract liabilities or deferred contract costs recorded in the Company's Consolidated Statements of Financial Condition. As a significant majority of the Company's revenue streams are not included in the scope of these ASUs and the recognition of revenue for the revenue streams within the scope of these ASUs are not significantly changed, the adoption of this guidance did not have a material impact on the Company's consolidated financial statements. Recently Issued Accounting Pronouncements In November 2018, the Financial Accounting Standards Board (the "FASB") issued ASU No. 2018-18, Collaborative Arrangements (Topic 808): Clarifying the Interaction between Topic 808 and Topic 606, which makes targeted improvements to the accounting for collaborative arrangements in response to questions raised as a result of the issuance of ASU 2014-09, Revenue from Contracts with Customers (Topic 606). The adoption of this ASU will be required beginning with TCF's Quarterly Report on Form 10-Q for the quarter ending March 31, 2020. Early adoption is allowed. The adoption of this guidance will not have a material impact on our consolidated financial statements. In October 2018, the FASB issued ASU No. 2018-17, Consolidation (Topic 810): Targeted Improvements to Related Party Guidance for Variable Interest Entities, which provides an elective exemption to private companies from applying variable interest entities ("VIE") guidance to all entities under common control if certain criteria are met. In addition, this ASU contains an amendment applicable to all entities which amends how a decision maker or service provider determines whether its fee is a variable interest in a VIE when a related party under common control also has an interest in the VIE. The adoption of this ASU will be required beginning with TCF's Quarterly Report on Form 10-Q for the quarter ending March 31, 2020. Early adoption is allowed. The adoption of this guidance will not have a material impact on our consolidated financial statements. In October 2018, the FASB issued ASU No. 2018-16, Derivatives and Hedging (Topic 815): Inclusion of the Secured Overnight Financing Rate (SOFR) Overnight Index Swap (OIS) Rate as a Benchmark Interest Rate for Hedge Accounting Purposes, which permits the use of the OIS Rate based on SOFR as a U.S. benchmark interest rate for hedge accounting purposes under Topic 815 in addition to the interest rates on direct Treasury obligations of the U.S. government, the LIBOR swap rate, the OIS Rate based on the Fed Funds Effective Rate and the Securities Industry and Financial Markets Association Municipal Swap Rate. The adoption of this ASU will be required beginning with TCF's Quarterly Report on Form 10-Q for the quarter ending March 31, 2019. Prospective application is required for qualifying new or redesignated hedging relationships entered into on or after the date of adoption. Early adoption is allowed. The adoption of this guidance will not have a material impact on our consolidated financial statements. In August 2018, the FASB issued ASU No. 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract (a consensus of the FASB Emerging Issues Task Force), which requires the decision to capitalize or expense implementation costs incurred in a cloud computing arrangement (i.e. a hosting arrangement) that is a service contract to follow the internal-use software guidance in Accounting Standards Codification ("ASC") 350-40. TCF's policy has been to expense these costs as incurred. The adoption of this ASU will be required beginning with TCF's Quarterly Report on Form 10-Q for the quarter ending March 31, 2020. Both retrospective and prospective application are allowed. Early adoption is allowed. Management has elected to early adopt this ASU beginning with the quarter ending March 31, 2019 on a prospective basis. The adoption of this guidance will not have a material impact on our consolidated financial statements. In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement, which eliminates, adds and modifies certain disclosure requirements for fair value measurements. The adoption of this ASU will be required beginning with TCF's Quarterly Report on Form 10-Q for the quarter ending March 31, 2020. Certain of the amendments require prospective application, while the remainder require retrospective application. Early adoption is allowed either for the entire standard or only the provisions that eliminate or modify the requirements. Management is currently evaluating the potential impact of this guidance on our consolidated financial statements. In June 2018, the FASB issued ASU No. 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting, which simplifies the accounting for share-based payments to nonemployees by aligning it more consistently with the accounting for share-based payments to employees. The new guidance in ASC 718 supersedes the guidance in ASC 505-50. The adoption of this ASU will be required on a modified retrospective basis with a cumulative effect adjustment required beginning with TCF's Quarterly Report on Form 10-Q for the quarter ending March 31, 2019. Early adoption is allowed. The adoption of this guidance will not have a material impact on our consolidated financial statements. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which changes the impairment model for most financial assets, including trade and other receivables, held to maturity debt securities, loans and purchased financial assets with credit deterioration. The ASU requires the use of a current expected credit loss ("CECL") approach to determine the allowance for credit losses for loans and held to maturity debt securities. CECL requires loss estimates for the remaining estimated life of the asset using historical loss data as well as reasonable and supportable forecasts based on current economic conditions. In November 2018, the FASB issued ASU No. 2018-19, Codification Improvements to Topic 326, Financial Instruments - Credit Losses, which clarifies that receivables arising from operating leases are not within the scope of Subtopic 326-20 and should be accounted for in accordance with Topic 842. The adoption of these ASUs will be required on a modified retrospective basis with a cumulative effect adjustment required beginning with TCF's Quarterly Report on Form 10-Q for the quarter ending March 31, 2020. Early adoption is allowed. Management is currently evaluating the potential impact of this guidance on our consolidated financial statements. CECL represents a significant change in GAAP and may result in a material impact to our consolidated financial statements. The impact of these ASUs will depend on the composition of TCF's portfolios and general economic conditions at the date of adoption. Additionally, there are several implementation questions which could affect the adoption impact once resolved. TCF has established a governance structure to implement these ASUs and is developing the methodologies and models to be used upon adoption. Management will begin to test the new methodologies and models in 2019. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), which, along with other amendments, requires lessees to recognize most leases on their balance sheet. Lessor accounting is largely unchanged. The ASU requires both quantitative and qualitative disclosure regarding key information about leasing arrangements from both lessees and lessors. In September 2017, the FASB issued ASU No. 2017-13, Revenue Recognition (Topic 605), Revenue from Contracts with Customers (Topic 606), Leases (Topic 840) and Leases (Topic 842): Amendments to SEC Paragraphs, which rescinds certain SEC Observer comments and staff announcements from the lease guidance and incorporates SEC staff announcements on the effect of a change in tax law on leveraged leases from ASC 840 into ASC 842. In January 2018, the FASB issued ASU No. 2018-01, Leases (Topic 842): Land Easement Practical Expedient for Transition to Topic 842, which amends the new lease guidance to add an optional transition practical expedient that permits an entity to continue applying its current accounting policy for land easements that exist or expire before Topic 842's effective date. In July 2018, the FASB issued ASU No. 2018-10, Codification Improvements to Topic 842, Leases, which makes narrow scope improvements to the standard for specific issues. In July 2018, the FASB also issued ASU No. 2018-11, Leases (Topic 842): Targeted Improvements, which provides an optional transition method allowing the standard to be applied at the adoption date and provides a practical expedient related to separating components of a contract for lessors. In December 2018, the FASB issued ASU No. 2018-20, Leases (Topic 842): Narrow-Scope Improvements for Lessors, which allows lessors to elect to account for all sales taxes as lessee costs, instead of determining whether they are lessee or lessor costs in each individual jurisdiction. It requires lessor costs paid by lessees directly to third parties to be excluded from revenue and requires lessors to account for costs excluded from the consideration of a contract that are paid by the lessor as revenue. It also requires certain variable payments to be allocated (rather than recognized) to lease and nonlease components when changes occur in the facts and circumstances on which the variable payments are based. The adoption of these ASUs will be required on a modified retrospective basis beginning with TCF’s Quarterly Report on Form 10-Q for the quarter ending March 31, 2019. Early adoption is allowed. Management has evaluated and will elect the practical expedients and optional transition method, which allow for existing leases to be accounted for consistent with current guidance and the new guidance applied at the adoption date. Management has evaluated TCF’s leasing contracts and activities and developed the methodologies and processes to estimate and account for the right-of-use assets and lease liabilities based on the present value of future lease payments. TCF adopted this guidance on January 1, 2019 by recording right-of-use assets and lease liabilities totaling $91.9 million and $112.8 million, respectively. While the increase to consolidated total assets resulting from the right-of-use assets recorded will increase TCF's risk-weighted assets, management does not expect the impact to capital ratios to be material. The adoption of this guidance is not expected to result in a material change to lessee expense recognition. The changes to lessor accounting, as well as changes in customer behavior driven by the adoption of these ASUs, could materially impact the results of TCF's lessor subsidiaries. Management expects earlier recognition of expense due to a narrower definition of initial direct costs and the timing of revenue recognition to be impacted for certain leases, resulting in more revenue being deferred over the lease term.