Goodwill and Other Intangible Assets - Rollforward of Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Finite-lived Intangible Assets [Roll Forward]
CDI and CRI Balance, beginning of period	$ 117,573	$ 117,573	$ 119,497	$ 117,573	$ 119,497
CDI and CRI Balance, end of period	109,646	117,573	119,497	109,646	119,497
Accumulated Amortization, beginning of period	(83,127)	(79,179)	(67,247)	(79,179)	(62,377)
Amortization	(3,882)	(3,948)	(4,870)	(7,830)	(9,740)
Accumulated Amortization, end of period	(79,082)	$ (83,127)	(72,117)	(79,082)	(72,117)
Net CDI and CRI, end of period	30,564		47,380	30,564	47,380
Finite Lived Intangible Assets Fully Amortized Portion	$ 7,927		$ 0	$ 7,927	$ 0