Derivative Instruments, Effective Portion Of Accumulated Loss at Discontinuance, Before Tax

No definition available.

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Line of Credit Facility, Additional Borrowing Capacity, Available

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No definition available.

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Amount of long-term debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Amount of assets pledged to secure a debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt premium.

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- Definition

Amount of advances from the Federal Home Loan Bank (FHLB).

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount of interest expense classified as other.

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No definition available.

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Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The loss recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

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- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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Debt (Details) - USD ($)				12 Months Ended
Debt (Details) - USD ($)	Jun. 29, 2018	Jun. 12, 2017	Feb. 24, 2015	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jul. 02, 2018	Jun. 30, 2018	Jun. 08, 2018	Feb. 27, 2014
Debt Instrument [Line Items]
Long-term Debt				$ 909,000,000	$ 592,300,000
Debt Instrument, Collateral Amount				15,700,000
Loss on Cash Flow Hedge Ineffectiveness				1,100,000
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months				(300,000)
Interest Expense				43,300,000	34,900,000	$ 44,400,000
Interest Paid, Including Capitalized Interest, Operating and Investing Activities				37,900,000	34,700,000	$ 44,200,000
Secured Debt [Member]
Debt Instrument [Line Items]
Debt instrument, face amount									$ 250,000,000
Issuance costs	$ 249,400,000
Notes Payable under Revolving Credit Agreement
Debt Instrument [Line Items]
Line of credit, outstanding				0
Subordinated Debt [Member] \| Subordinated Debenture, 7.375 Percent Due 2054 [Member]
Debt Instrument [Line Items]
Stated interest rate, percentage										7.375%
Senior Notes [Member] \| Senior Notes, 4.35 Percent Due February 15, 2025 [Member]
Debt Instrument [Line Items]
Long-term Debt				450,000,000
Debt instrument, face amount		$ 200,000,000	$ 250,000,000.0
Stated interest rate, percentage			4.35%
Issuance costs		$ 200,200,000	$ 247,300,000
Interest rate, effective percentage		4.16%	4.49%
Senior Notes [Member] \| Senior Notes, 6% Due November 30, 2015 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount			$ 250,000,000
Stated interest rate, percentage			6.00%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity									300,000,000
Revolving Credit Facility [Member] \| Credit facility and Secured Loan [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Additional Borrowing Capacity, Available									$ 100,000,000
Federal Home Loan Bank of Chicago [Member]
Debt Instrument [Line Items]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances				10,000,000	0			$ 55,000,000
Federal Home Loan Bank Stock				800,000	400,000
Federal Home Loan Bank of Dallas [Member]
Debt Instrument [Line Items]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances				0	0			$ 55,000,000
Federal Home Loan Bank Stock				3,300,000	$ 3,300,000
Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member]
Debt Instrument [Line Items]
Derivative Instruments, Effective Portion Of Accumulated Loss at Discontinuance, Before Tax				4,500,000
Interest Expense, Other				$ 300,000
Infinity [Member] \| Senior Notes [Member] \| Senior Note Due on September Nineteen,Twenty Twenty Two [Member]
Debt Instrument [Line Items]
Debt instrument, face amount							$ 275,000,000
Stated interest rate, percentage							5.00%
Interest rate, effective percentage							4.36%
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt							$ 282,100,000
Debt Instrument, Unamortized Premium							$ 7,100,000