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

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

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

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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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 carrying amount, as of the date of the latest financial statement presented, of loans receivable which are owned but transferred to serve as collateral for the payment of FHLB debt obligations, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

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Medium- And Long-Term Debt (Narrative) (Details) (USD $)	3 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2014
Debt Instruments [Line Items]
Gain on debt redemption	$ 32,000,000	$ 32,000,000	$ 1,000,000	$ 0
Blanket lien on real-estate related loans securing FHLB advances		14,000,000,000
FHLB potential future borrowings		6,000,000,000
Parent Company \| 2.125% notes due 2019
Debt Instruments [Line Items]
Stated interest rate		2.125%			2.125%
Notes issued					350,000,000
Parent Company \| 3.80% subordinated notes due 2026
Debt Instruments [Line Items]
Stated interest rate	3.80%	3.80%
Notes issued	250,000,000
Subsidiaries \| 8.375% subordinated notes due 2014
Debt Instruments [Line Items]
Stated interest rate	8.375%
Par value of subordinated notes called	$ 150,000,000