Trust preferred securities included in tier one capital percent.

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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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No definition available.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Latest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

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Earliest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

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Description of debt redemption features under terms of the debt agreement.

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Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

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The cash outflow for a long-term debt where the holder has highest claim on the entity's asset in case of bankruptcy or liquidation during the period.

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- Definition

Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of securities pledged as collateral against securities sold under agreement to repurchase.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Borrowings - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	6 Months Ended
	May 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Junior subordinated debentures		$ 518
Trust preferred capital securities		0.00%
Debt Maturity, Start Year		Jan. 01, 2027
Debt Maturity, End Year		Dec. 31, 2033
Agreements to repurchase securities		$ 428	$ 1,100
Collateral posted		$ 448	$ 1,100
Bank Note Program [Member]
Debt Instrument [Line Items]
Senior notes	$ 900
Debt instrument maturity year	May 31, 2022
Bank Note Program Fixed Interest Rate [Member]
Debt Instrument [Line Items]
Senior notes	$ 650
Fixed interest rate	2.50%
London Interbank Offered Rate (LIBOR) [Member] \| Bank Note Program Variable Interest Rate [Member]
Debt Instrument [Line Items]
Senior notes	$ 250
Fixed Rate Senior Notes [Member]
Debt Instrument [Line Items]
Fixed interest rate		1.40%
Debt instrument maturity year		Jul. 25, 2017
Repayments of senior notes		$ 750
Debt instrument, redemption, description		The notes had a maturity date of July 25, 2017 and were redeemable on or after the 30th day prior to the maturity date.