Leases - Lease Expense Components (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Leases [Abstract]
Operating lease cost	$ 9,518
Short-term lease cost	263
Variable lease cost	846
Less: sublease income	(1,108)
Total lease cost, net	$ 9,519
Weighted-average remaining term (in years) - operating leases	6 years 4 months 24 days
Weighted-average discount rate - operating leases	3.18%
Cash paid for operating leases	$ 10,354

No definition available.

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Amount of operating lease expense. Excludes sublease income.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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Amount of cash outflow for short-term lease payment excluded from lease liability.

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Amount of sublease income excluding finance and operating lease expense.

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Amount of cash outflow for variable lease payment excluded from lease liability.

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