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Multiemployer Benefit Plans (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
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Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Multiemployer Pension Plans [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Multiemployer Plan, Period Contributions | $ 215 | $ 229 | $ 209
Multiemployer Plans Period Contributions Significance Of Contributions | false |  |
Multiemployer Health Plans [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Multiemployer Plan, Period Contributions | $ 731 | $ 735 | $ 703

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- Definition Description of whether the employer's contributions represent more than five percent of total contributions to the multiemployer plan for the most recent plan year available. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. + References No definition available. + Details
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- Definition Amount of contributions made to multiemployer plans for each period for which a statement of income is presented. An employer may disclose total contributions to multiemployer plans without disaggregating the amounts attributable to pension plans and other postretirement benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 12 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Section 50 -Paragraph 1 -SubTopic 80 -Topic 715 -URI http://asc.fasb.org/extlink&oid=6958064&loc=d3e29142-114947 + Details
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