Leases Lease Costs (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) Rate
Leases [Abstract]
Lease, Cost	$ 8,217
Operating Lease, Expense	9,533
Variable Lease, Cost	925
Short-term Lease, Cost	$ 391
Operating Lease, Weighted Average Remaining Lease Term	6 years 9 months 18 days
Operating Lease, Weighted Average Discount Rate, Percent \| Rate	3.00%

Amount of lease cost recognized by lessee for lease contract.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

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- References

No definition available.

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- Definition

Amount of operating lease expense. Excludes sublease income.

+ References

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- Definition

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

+ References

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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.

+ References

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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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