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Operating Leases - Additional Information (Detail) - USD ($) $ in Millions |  | 12 Months Ended |
--- | --- | --- | ---
Jan. 01, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2019
Leases [Abstract] |  |  |  |
Operating lease right-of-use assets |  |  |  | $ 111.1
Operating lease right-of-use assets, accumulated amortization |  |  |  | $ 20.6
ROU assets and operating lease liabilities in connection with adoption of new lease standard | $ 76.7 |  |  |
Reclassification of prepaid rent and deferred rent to ROU assets in connection with adoption of new lease standard | $ 7.8 |  |  |
Deferred rent |  | $ 5.6 |  |
Rental expense |  | $ 27.7 | $ 25.6 |

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- Definition Accumulated Amortization Of Right Of Use Lease Assets + References No definition available. + Details
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- Definition New accounting pronouncements reclassification of prepaid rent and deferred rent to right of use assets + References No definition available. + Details
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- Definition New accounting pronouncements right of use assets and operating lease liabilities. + References No definition available. + Details
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- Definition Operating Lease Right Of Use Asset Gross + References No definition available. + Details
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- Definition The cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property by the lessor or lessee, respectively. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77902458&loc=d3e39896-112707 + Details
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- References No definition available. + Details
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- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717 + Details
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