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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate 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 stock repurchase plan authorized.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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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

+ Details

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Period Type:	duration

- 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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- Details

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Stock Repurchases - Additional Information (Details) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	12 Months Ended			29 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014	Aug. 31, 2012	Nov. 30, 2014
Equity, Class of Treasury Stock [Line Items]
Total number of shares repurchased	884us-gaap_TreasuryStockSharesAcquired	885us-gaap_TreasuryStockSharesAcquired	898us-gaap_TreasuryStockSharesAcquired
Dollar amount of shares repurchased	$ 24,091,000	$ 20,962,000	$ 12,363,000
Average price paid per share	$ 27.24	$ 23.70	$ 13.76
Stock repurchases program, remaining authorized repurchase amount	54,900,000			54,900,000
August 2012 Stock Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Stock repurchases program, authorized amount					50,000,000
Stock repurchases program, amount repurchased				45,100,000
November 2014 Stock Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Stock repurchases program, authorized amount						$ 50,000,000