| Shareholders' Equity (Details) (USD $) | 3 Months Ended | 6 Months Ended | 0 Months Ended | ||
|---|---|---|---|---|---|
| Jun. 30, 2012 | Jun. 30, 2011 | Jun. 30, 2012 | Jun. 30, 2011 | Jul. 24, 2012
 Dividend Declared [Member] | |
| Stockholders' Equity Note [Abstract] | |||||
| Number of shares authorized to be repurchased (in shares) | 2,000,000 | 2,000,000 | |||
| Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased (in shares) | 815,059 | 815,059 | |||
| Shareholders' Equity [Line Items] | |||||
| Dividends per share (in dollars per share) | $ 0.07 | $ 0.07 | $ 0.14 | $ 0.14 | $ 0.10 | 
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- Definition Aggregate dividends declared during the period for each share of common stock outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
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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. No definition available. 
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- Definition The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan. No definition available. 
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