Leases Costs and Supplemental Information (Details) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019 USD ($)	Sep. 30, 2019 USD ($)
Leases [Abstract]
Operating lease expense	$ 4,654	$ 14,140
Variable lease expense	786	2,156
Sublease income	(239)	(610)
Total lease expense	5,201	15,686
ROU assets	104,746	104,746
Lease liabilities	$ 111,617	$ 111,617
Weighted average remaining lease term	8 years 3 months 18 days	8 years 3 months 18 days
Weighted average discount rate	3.05%	3.05%
Cash paid for amounts included in the measurement of lease liabilities		$ 13,913
ROU assets obtained in exchange for lease obligations		$ 115,681