Percentage of face value of repurchased preferred stock.

No definition available.

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- Definition

Term of warrant in years

+ References

No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.4-08.(i)(4))

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- Definition

Number of warrants or rights outstanding.

+ References

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- Definition

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

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-Topic 210

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-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share.

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-Publisher FASB

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-Name Regulation S-X (SX)

-Number 210

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-Number 210

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-Article 4

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-Topic 235

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-Subparagraph (SX 210.4-08.(d)(1))

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+ Details

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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

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-Paragraph 1

-Subparagraph (SX 210.5-02.28)

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- Definition

Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

+ References

+ Details

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- Definition

Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

+ References

+ Details

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- Definition

Value of all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by shareholders, which is net of related treasury stock. May be all or a portion of the number of preferred shares authorized. These shares represent the ownership interest of the preferred shareholders.

+ References

+ Details

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

+ Details

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- Definition

Amount of a stock repurchase plan authorized by an entity's Board of Directors.

+ References

No definition available.

+ Details

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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- Definition

Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(i))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph i

-Article 4

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- Details

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Common and Preferred Stock (Narrative) (Detail) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended		0 Months Ended		95 Months Ended	0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	May 06, 2013	Feb. 01, 2007	Dec. 31, 2014	Nov. 05, 2014	Aug. 05, 2013	Dec. 31, 2008
Class of Stock [Line Items]
Fair value of warrants	$ 28us-gaap_WarrantsAndRightsOutstanding	$ 59us-gaap_WarrantsAndRightsOutstanding			$ 28us-gaap_WarrantsAndRightsOutstanding
Treasury stock value acquired cost method	35	7
Preferred stock shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued			0us-gaap_PreferredStockSharesIssued
Preferred stock shares outstanding	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding			0us-gaap_PreferredStockSharesOutstanding
Preferred Stock Par Or Stated Value Per Share	$ 1	$ 1			$ 1
Blue Ridge [Member]
Class of Stock [Line Items]
Warrants outstanding			9,940,000
Warrant exercise price			9.59
Warrant Term			5 years
Preferred Stock [Member] \| MBIA Insurance Corporation [Member]
Class of Stock [Line Items]
Shares repurchased under share repurchase program, average price per share	$ 10,900.00
Preferred stock shares issued	2,759				2,759
Preferred stock repurchased during period shares	1,444
Preferred stock, carrying value issued and outstanding	28				28
Face value of repurchased preferred stock	10.90%
Preferred Stock Par Or Stated Value Per Share	$ 1,000				$ 1,000
Preferred stock liquidation preference	$ 100,000				$ 100,000
Dividend rate on preferred stock determined rate	LIBOR plus 200 basis points
2007 Repurchase Authorization [Member]
Class of Stock [Line Items]
Authorized repurchase of common stock, value				1,000
Treasury stock shares acquired	2,100,000				58,800,000
Shares repurchased under share repurchase program, average price per share					$ 17.02
2014 Repurchase Authorization [Member]
Class of Stock [Line Items]
Authorized repurchase of common stock, value						$ 200
Treasury stock shares acquired	1,200,000
Shares repurchased under share repurchase program, average price per share	$ 9.44
Unaffiliated Investors [Member] \| MBIA Insurance Corporation [Member]
Class of Stock [Line Items]
Preferred stock shares outstanding	1,315				1,315
Long-Term Incentive Plan [Member]
Class of Stock [Line Items]
Treasury stock shares acquired	529,246	392,056
Warrant [Member] \| Warburg Pincus [Member]
Class of Stock [Line Items]
Warrants outstanding							11,800,000	11,500,000
Warrant exercise price							29.44	30.25
B Warrants [Member] \| Warburg Pincus [Member]
Class of Stock [Line Items]
Warrants outstanding							10,100,000	9,800,000
Warrant exercise price							29.44	30.25
B2 Warrants [Member] \| Warburg Pincus [Member]
Class of Stock [Line Items]
Warrants outstanding							4,004,945	4,000,000
Warrant exercise price							16.18	16.2
Grossup Warrant [Member] \| Warburg Pincus [Member]
Class of Stock [Line Items]
Warrants outstanding							1,910,000
Warrant exercise price							9.59
Warrant Term							5 years