Percentage of outstanding common stock repurchased had there been no repurchases.

No definition available.

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ 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

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28,29)

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-Number 210

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-Paragraph 29, 30

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- Definition

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

+ References

+ Details

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- Definition

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.

+ References

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

-Publisher FASB

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-Topic 505

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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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

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Treasury Stock and Subsequent Event - Additional Information (Detail) (USD $)	3 Months Ended	9 Months Ended	1 Months Ended
	Dec. 31, 2014	Dec. 31, 2014	Jan. 30, 2015	Mar. 31, 2014	Aug. 31, 2013
Class of Stock [Line Items]
Treasury stock, value	$ 351,132,000us-gaap_TreasuryStockValue	$ 351,132,000us-gaap_TreasuryStockValue		$ 328,480,000us-gaap_TreasuryStockValue
Treasury stock, shares	32,731,909us-gaap_TreasuryStockShares	32,731,909us-gaap_TreasuryStockShares		32,147,474us-gaap_TreasuryStockShares
Common stock equals to percentage of outstanding common stock		62.00%
Average price		$ 10.73
Common stock outstanding	20,474,606us-gaap_CommonStockSharesOutstanding	20,474,606us-gaap_CommonStockSharesOutstanding		20,979,392us-gaap_CommonStockSharesOutstanding
Common stock repurchased shares	274,483us-gaap_TreasuryStockSharesAcquired	584,435us-gaap_TreasuryStockSharesAcquired
Purchase of treasury stock	9,500,000	22,600,000
Minimum [Member]
Class of Stock [Line Items]
Number of shares authorized to repurchase					2,000,000
Maximum [Member]
Class of Stock [Line Items]
Number of shares authorized to repurchase					34,000,000
Subsequent Event [Member]
Class of Stock [Line Items]
Average price			$ 34.93
Common stock repurchased shares			85,846
Purchase of treasury stock			$ 3,000,000