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

+ References

No definition available.

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

+ References

+ Details

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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

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 4: 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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Balance Type:	debit
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Treasury Stock - Additional Information (Detail) (USD $)	12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013	Jun. 12, 2015	Aug. 31, 2013
Class of Stock [Line Items]
Common stock repurchased shares	845,014us-gaap_TreasuryStockSharesAcquired	830,460us-gaap_TreasuryStockSharesAcquired	1,410,812us-gaap_TreasuryStockSharesAcquired
Purchase of treasury stock	$ 31,798,000	$ 27,179,000	$ 30,727,000
Average price	$ 37.63	$ 32.73	$ 21.78
Subsequent Event [Member]
Class of Stock [Line Items]
Common stock repurchased shares	182,113			182,113
Purchase of treasury stock	$ 6,500,000			$ 6,500,000
Average price	$ 35.89			$ 35.89
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