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Multiemployer Benefit Plans (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Multiemployer Plans [Line Items] |  |  |
Multiemployer Plans Period Contributions Significance Of Contributions | false |  |
Multiemployer Pension Plans [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Multiemployer Plan, Period Contributions | $ 196 | $ 215 | $ 229
Multiemployer plan period contributions from continuing operations | 135 | 140 | 149
Multiemployer Health Plans [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Multiemployer Plan, Period Contributions | 734 | 731 | 735
Multiemployer plan period contributions from continuing operations | $ 484 | $ 480 | $ 510

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- Definition Multiemployer plan period contributions relating to continuing operations. + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
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Period Type: | duration

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- Definition Amount of contributions made to multiemployer plans by the employer. 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 Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450702-114947 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450691-114947 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450657-114947 + Details
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Period Type: | duration

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- Details
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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 Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (e)(2) -URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450657-114947 + Details
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