Leases - Components of Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Leases
Operating Lease Cost	$ 1,406	$ 1,481
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from operating leases	1,486	1,395
Right-of-use assets obtained in exchange for new operating lease liabilities	15	$ 719
Other non-cash reductions to right of use assets	1,192
Operating lease right-of-use assets	$ 19,889		$ 22,335
Operating lease, right-of-use asset, Statement of Financial Position	us-gaap:OtherAssets
Operating Lease Liabilities	$ 23,141		$ 24,475
Operating lease liability, Statement of Financial Position	us-gaap:OtherLiabilities
Weighted-average remaining lease term - operating leases	4 years 5 months 23 days		4 years 8 months 8 days
Weighted-average discount rate - operating leases	2.34%		2.33%
Minimum
Leases
Remaining lease terms - operating leases	1 year
Maximum
Leases
Remaining lease terms - operating leases	15 years