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Property and Equipment - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Property, Plant and Equipment [Line Items] |  |  |  |
Impairment charge |  |  |  | $ 12.6
Depreciation expense | 13.0 | 13.8 | 15.0 |
Land and Building [Member] |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Impairment charge |  | $ 1.7 |  |

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- Definition Depreciation Expense And Amortization Of Leased Assets + References No definition available. + Details
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- Definition Loss recognized as a result of the initial and subsequent write-down of a long-lived asset's carrying amount to fair value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2921-110230 + Details
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- Details
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