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           Acquisitions - Summary of Final Amounts Allocated to Acquired Assets and Assumed Liabilities (Parenthetical) (Detail) (Ten-Sixty) 
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        6 Months Ended | 
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           Jun. 30, 2014 
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           Customer Relationships 
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| Business Acquisition [Line Items] | |
| Intangible asset life | 10 years | 
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           Non-compete Agreements 
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| Business Acquisition [Line Items] | |
| Intangible asset life | 5 years | 
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- Definition 
          Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
          
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