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Profit Sharing Plan (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Deferred Compensation Arrangements [Abstract] |  |  |
Maximum percentage of compensation employee is allowed to contribute | 15.00% |  |
Matching contributions | $ 7.2 | $ 7.2 | $ 7.0
Value of shares authorized to repurchase for ESOP allocation | $ 0 | $ 0 | $ 1.2

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- Definition Maximum percentage of compensation employee is allowed to contribute to the Plan. + References No definition available. + Details
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- Details
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- Definition The amount of payment into the fund established for purposes of making future disbursements to the individual in accordance with the terms and understanding of the deferred compensation arrangement. + References No definition available. + Details
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- Definition An entity will typically disclose the amount of any repurchase obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 40 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=6418621&loc=d3e17540-113929 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 93-6 -Paragraph 53 -Subparagraph f -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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