Significant Accounting Policies

Nature of Operations. Cullen/Frost Bankers, Inc. (“Cullen/Frost”) is a financial holding company and a bank holding company headquartered in San Antonio, Texas that provides, through its subsidiaries, a broad array of products and services throughout numerous Texas markets. The terms “Cullen/Frost,” “the Corporation,” “we,” “us” and “our” mean Cullen/Frost Bankers, Inc. and its subsidiaries, when appropriate. In addition to general commercial and consumer banking, other products and services offered include trust and investment management, insurance, brokerage, mutual funds, leasing, treasury management, capital markets advisory and item processing.

Basis of Presentation. The consolidated financial statements in this Quarterly Report on Form 10-Q include the accounts of Cullen/Frost and all other entities in which Cullen/Frost has a controlling financial interest. All significant intercompany balances and transactions have been eliminated in consolidation. The accounting and financial reporting policies we follow conform, in all material respects, to accounting principles generally accepted in the United States and to general practices within the financial services industry.

The consolidated financial statements in this Quarterly Report on Form 10-Q have not been audited by an independent registered public accounting firm, but in the opinion of management, reflect all adjustments necessary for a fair presentation of our financial position and results of operations. All such adjustments were of a normal and recurring nature. The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States for interim financial information and with the instructions to Form 10-Q adopted by the Securities and Exchange Commission (“SEC”). Accordingly, the financial statements do not include all of the information and footnotes required by accounting principles generally accepted in the United States for complete financial statements and should be read in conjunction with our consolidated financial statements, and notes thereto, for the year ended December 31, 2017, included in our Annual Report on Form 10-K filed with the SEC on February 7, 2018 (the “2017 Form 10-K”). Operating results for the interim periods disclosed herein are not necessarily indicative of the results that may be expected for a full year or any future period.

Use of Estimates. The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements. Actual results could differ from those estimates. The allowance for loan losses and the fair values of financial instruments and the status of contingencies are particularly subject to change.

Cash Flow Reporting. Additional cash flow information was as follows:



	Nine Months Ended September 30,
	2018		2017
Cash paid for interest	$	59,764	$	15,611
Cash paid for income taxes	5,112		41,969
Significant non-cash transactions:
Unsettled purchases/sales of securities	74,191		41,763
Loans foreclosed and transferred to other real estate owned and foreclosed assets	2,898		257

Accounting Changes, Reclassifications and Restatements. Certain items in prior financial statements have been reclassified to conform to the current presentation. In addition, we adopted ASU 2018-02, "Income Statement - Reporting Comprehensive Income (Topic 220) - Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income" as of January 1, 2018. In accordance with ASU 2018-02, we elected to reclassify certain income tax effects related to the change in the U.S. statutory federal income tax rate under the Tax Cuts and Jobs Act, which was enacted on December 22, 2017 (see Note 13 - Income Taxes), from accumulated other comprehensive income to retained earnings. Such amounts, which totaled $9.5 million, related to a net actuarial loss on defined benefit post-retirement plans and unrealized gains on securities available for sale and securities transferred to held to maturity. See Note 14 - Other Comprehensive Income. The effects of the Tax Cuts and Jobs Act on deferred taxes related to amounts initially recorded in accumulated other comprehensive income are provisional. As we finalize the accounting for the tax effects of the Tax Cuts and Jobs Act, additional reclassification adjustments may be recorded in future periods. See Note 13 - Income Taxes. Notwithstanding this election made in accordance with ASU 2018-02, our policy is to release such income tax effects only when the entire portfolio to which the underlying transactions relate is liquidated, sold or extinguished.

We also adopted ASU 2014-09, "Revenue from Contracts with Customers (Topic 606)” as of January 1, 2018. Using a modified retrospective transition approach for contracts that were not complete as of our adoption, we recognized a cumulative effect reduction to beginning retained earnings totaling $2.3 million. The amount was related to certain revenue streams within trust and investment management fees. Additionally, based on our underlying contracts, ASU 2014-09 requires us to report network costs associated with debit card and ATM transactions netted against the related fee income from such transactions. Previously, such network costs were reported as a component of other non-interest expense. For the three and nine months ended September 30, 2018, gross interchange and debit card transaction fees totaled $6.5 million and $19.0 million, respectively, while related network costs totaled $3.0 million and $8.9 million, respectively. On a net basis, we reported $3.5 million and $10.1 million as interchange and debit card transaction fees in the accompanying Consolidated Statement of Income for the three and nine months ended September 30, 2018, respectively. For the three and nine months ended September 30, 2017, we reported interchange and debit card transaction fees totaling $5.9 million and $17.2 million, respectively, on a gross basis in the accompanying Consolidated Statement of Income while related network costs totaling $3.0 million and $9.1 million were reported as a component of other non-interest expense for the three and nine months ended September 30, 2017, respectively. ASU 2014-09 also required us to change the way we recognize certain recurring revenue streams reported as components of trust and investment management fees, insurance commissions and fees and other categories of non-interest income, however, such changes were not significant to our financial statements for the nine months ended September 30, 2018.

Under ASU 2014-09, we adopted new policies related to revenue recognition. In general, for revenue not associated with financial instruments, guarantees and lease contracts, we apply the following steps when recognizing revenue from contracts with customers: (i) identify the contract, (ii) identify the performance obligations, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations and (v) recognize revenue when performance obligation is satisfied. Our contracts with customers are generally short term in nature, typically due within one year or less or cancellable by us or our customer upon a short notice period. Performance obligations for our customer contracts are generally satisfied at a single point in time, typically when the transaction is complete, or over time. For performance obligations satisfied over time, we primarily use the output method, directly measuring the value of the products/services transferred to the customer, to determine when performance obligations have been satisfied. We typically receive payment from customers and recognize revenue concurrent with the satisfaction of our performance obligations. In most cases, this occurs within a single financial reporting period. For payments received in advance of the satisfaction of performance obligations, revenue recognition is deferred until such time the performance obligations have been satisfied. In cases where we have not received payment despite satisfaction of our performance obligations, we accrue an estimate of the amount due in the period our performance obligations have been satisfied. For contracts with variable components, only amounts for which collection is probable are accrued. We generally act in a principal capacity, on our own behalf, in most of our contracts with customers. In such transactions, we recognize revenue and the related costs to provide our services on a gross basis in our financial statements. In some cases, we act in an agent capacity, deriving revenue through assisting other entities in transactions with our customers. In such transactions, we recognized revenue and the related costs to provide our services on a net basis in our financial statements. These transactions primarily relate to insurance and brokerage commissions and fees derived from our customers' use of various interchange and ATM/debit card networks.

In August 2018, the Securities and Exchange Commission (“SEC”) issued Final Rule Release No. 33-10532 - “Disclosure Update and Simplification.” This rule amends various SEC disclosure requirements that have been determined to be redundant, duplicative, overlapping, outdated, or superseded. The changes are generally expected to reduce or eliminate certain disclosures; however, the amendments did expand interim period disclosure requirements related to changes in shareholders' equity. Although the final rule does not become effective until November 5, 2018, we elected to expand our presentation of the Statement of Changes in Shareholders' Equity, as will be required under the new rule, in our financial statements as of and for the three and nine months ended September 30, 2018.