Consolidated Statements of Changes in Stockholders' Equity (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Unrealized gain (loss) on derivatives tax (benefit) expense	$ (286)	$ 632
Cash dividends declared per share	$ 0.62	$ 0.60	$ 6.07
Repurchase of treasury stock, Shares	2,605,970us-gaap_TreasuryStockSharesAcquired	1,500,000us-gaap_TreasuryStockSharesAcquired
Accumulated Other Comprehensive (Loss) Income [Member]
Unrealized gain (loss) on derivatives tax (benefit) expense	$ (286)	$ 632	$ (627)

Aggregate dividends declared during the period for each share of common stock outstanding.

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 S99

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+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (d)

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

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

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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

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-Name Accounting Standards Codification

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

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