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Commitments and Contingencies - Additional Information (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract] |  |  |
Rental expense | $ 87,500,000 | $ 87,300,000 | $ 85,900,000
Rodriguez Case |  |  |
Loss Contingencies [Line Items] |  |  |
Allegations loss | 0 |  |
Gentry Case |  |  |
Loss Contingencies [Line Items] |  |  |
Allegations loss | $ 0 |  |

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- Definition Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line. + References No definition available. + Details
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