Amount of cash receipt from (payment to) bank; or stock received from (issuance to) bank in the settlement of the accelerated share repurchase agreement.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 25

-Paragraph 5

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

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

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The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury.

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Shareholders' Equity - Additional Information (Detail) (USD $)	0 Months Ended	12 Months Ended
	Oct. 08, 2014	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 02, 2014	Jul. 21, 2014
Equity, Class of Treasury Stock [Line Items]
Shares repurchased, authorized amount			$ 25,000,000
Shares repurchased, number of shares received initially		2,385,000us-gaap_TreasuryStockShares		0us-gaap_TreasuryStockShares
Fair value of common stock repurchased		75,025,000us-gaap_TreasuryStockValue
Accelerated Share Repurchase Agreement [Member]
Equity, Class of Treasury Stock [Line Items]
Shares repurchased, aggregate repurchase amount	50,000,000				50,000,000
Shares repurchased, remaining amount	7,500,000
Shares repurchased, number of shares received initially	246,000				1,293,760
Fair value of common stock repurchased					42,500,000
Total number of shares repurchased	1,539,760	2,384,760
Maximum [Member]
Equity, Class of Treasury Stock [Line Items]
Shares repurchased, authorized amount						$ 200,000,000