Maximum exposure to loss unconsolidated VIE unamortized investments.

No definition available.

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- Definition

Variable interest entity assets of unconsolidated operating partnerships.

+ References

No definition available.

+ Details

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- Definition

Variable interest entity maximum exposure to loss recapture tax credits claim.

+ References

No definition available.

+ Details

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- Definition

Variable interest entity settlement value of third party interests.

+ References

No definition available.

+ Details

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- Definition

Variable interest entity settlement value of third party interests including reserves.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Total assets of operating partnerships that are held by the consolidated guaranteed funds.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(h))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph h

-Article 7

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount deducted from an entities' taxes, reflecting a percentage of an amount invested in certain assets spread over the useful life of those assets; includes deferred investment tax credits.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (bb)

-URI http://asc.fasb.org/extlink&oid=28200181&loc=d3e5710-111685

+ Details

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Balance Type:	debit
Period Type:	instant

- Details

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- Definition

Carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph a

-URI http://asc.fasb.org/extlink&oid=28200181&loc=d3e5728-111685

+ Details

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Balance Type:	debit
Period Type:	instant

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Variable Interest Entities - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
LIHTC Funds [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Carrying Amount of Assets, Consolidated VIEs	$ 1,000,000	$ 15,000,000	$ 1,000,000
Settlement value of third-party interests, reserves	5,000,000
Variable Interest Entity, Carrying Amount of Assets, Unconsolidated VIE	55,000,000	97,000,000	55,000,000
LIHTC Funds [Member] \| Minimum [Member]
Variable Interest Entity [Line Items]
Settlement value of third-party interests, approximately	0
LIHTC Funds [Member] \| Maximum [Member]
Variable Interest Entity [Line Items]
Settlement value of third-party interests, approximately	4,000,000
LIHTC Funds [Member] \| Investments [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Carrying Amount of Assets, Consolidated VIEs		12,000,000	5,000,000
LIHTC Funds [Member] \| Investments [Member] \| Maximum [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Carrying Amount of Assets, Consolidated VIEs	1,000,000
LIHTC Investments [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Carrying Amount of Assets, Unconsolidated VIE	1,355,000,000	1,595,000,000	1,234,000,000
Assets of unconsolidated LIHTC operating partnerships	885,000,000	826,000,000	764,000,000
Maximum exposure to loss, unconsolidated VIE	397,000,000
Recapture tax claim	108,000,000
Tax credit of investment	28,000,000	27,000,000
Additional investments in unconsolidated LIHTC operating partnerships held by consolidated LIHTC	470,000,000	769,000,000	470,000,000
Investment in LIHTC	1,000,000,000	960,000,000
LIHTC Investments [Member] \| Return Guarantee Agreement with LIHTC Investors [Member]
Variable Interest Entity [Line Items]
Tax credit of investment	4,000,000
LIHTC Investments [Member] \| Investments [Member]
Variable Interest Entity [Line Items]
Amortization of investment	$ 25,000,000	$ 24,000,000