Change in fair value of nonrecurring fair value measured loans for charge-offs and impairment reserves.

No definition available.

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- Definition

Fair value of securities issued by financial institutions and other entities backed by trust preferred securities.

+ References

No definition available.

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- Definition

Number Of Independent Pricing Sources Used To Value Privately Issued Mortgage Backed Securities Valued With Internal Modeling

+ References

No definition available.

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- Definition

Securities issued by financial institutions and other entities backed by trust preferred securities at cost.

+ References

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Percentage of adjustment to the observed price for a similar asset or liability when an identical transaction does not exist, used as an input to measure fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Carrying amount as of the balance sheet date of all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance; includes real and personal property; equity interests in corporations, partnerships, and joint ventures; and beneficial interests in trusts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4437-111522

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Glossary Loan

-URI http://asc.fasb.org/extlink&oid=6517073

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- Definition

The amount of other than temporary impairment losses on investments in debt securities categorized as Held-to-maturity which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) of investments in debt securities due to credit losses and other than temporary impairments due to other than credit losses when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

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Fair Value Measurements - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of independent pricing sources used to value privately issued mortgage-backed securities valued with internal modeling	2
Securities issued by financial institutions and other entities backed by trust preferred securities at cost	$ 30	$ 42
Fair value of securities issued by financial institutions and other entities backed by trust preferred securities	50	63
Other-than-temporary losses			5
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in fair value of nonrecurring fair value measured loans for charge-offs and impairment reserves	55	58	67
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans measured at fair value on nonrecurring basis	173	222	335
Assets taken in foreclosure of defaulted loans measured at fair value on a nonrecurring basis	19	29
Fair Value, Measurements, Nonrecurring [Member] \| Significant Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans measured at fair value on nonrecurring basis	94	173	207
Fair Value, Measurements, Nonrecurring [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans measured at fair value on nonrecurring basis	$ 79	$ 49	$ 128
Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount margin over LIBOR	5.00%
Discount rates for fair value estimations	15.00%
Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount margin over LIBOR	10.00%
Discount rates for fair value estimations	90.00%
Weighted Average [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount margin over LIBOR	8.00%