Leases Lessee Cost (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Lease, Cost [Abstract]
Operating lease costs	$ 7,381	$ 7,512	$ 22,212	$ 22,384
Variable lease costs	1,297	1,292	4,217	3,613
Sublease income	(141)	(142)	(428)	(437)
Total operating lease cost	8,537	8,662	26,001	25,560
Cash paid for amounts included in the measurement of lease liabilities	7,823	7,938	23,359	23,349
ROU lease assets obtained in exchange for new operating lease liabilities	$ 856	$ 9,983	$ 9,552	$ 22,917
Weighted-average remaining lease term - operating leases, in years	8 years 2 months 23 days		8 years 2 months 23 days
Weighted-average discount rate - operating leases	3.22%		3.22%