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

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- Definition

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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Face (par) amount of the original debt instrument that was repurchased.

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- Definition

Gross amount of debt extinguished.

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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Amount of gain (loss) from the difference between the repurchase price of a debt instrument initially issued by the entity and the net carrying amount of the debt at the time of its repurchase.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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Long-term Debt and Short Term Borrowings (Narrative) (Details) - USD ($)		3 Months Ended	12 Months Ended
	Nov. 01, 2017	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Loss on early extinguishment of debt		$ 23,200,000	$ 23,160,000	$ 4,735,000	$ 1,533,000
Loans Receivable
Debt Instrument [Line Items]
Recorded balance loans receivable		3,400,000,000	3,400,000,000	3,250,000,000
3.125% Senior Notes due November 1, 2022
Debt Instrument [Line Items]
Debt, face amount	$ 300,000,000.0	$ 300,000,000	$ 300,000,000
Stated percentage	3.125%	3.125%	3.125%
Proceeds from issuance of debt	$ 296,900,000
7.875% Senior Notes due February 15, 2019
Debt Instrument [Line Items]
Debt, face amount				$ 300,000,000.0
Stated percentage				7.875%
Loss on early extinguishment of debt			$ 23,200,000
5.125% Subordinated Notes due June 15, 2017
Debt Instrument [Line Items]
Extinguishment of debt, amount			$ 278,600,000
Repurchased face amount				$ 124,700,000.0	46,700,000.0
Loss on repurchase of debt				$ 4,700,000	$ 1,500,000