Goodwill and Other Intangible Assets - Other Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	$ 201,316	$ 199,932
Accumulated Amortization	(118,474)	(113,113)
Valuation Allowance	(156)	(47)
Net Intangible Assets	82,686	86,772
Loan servicing rights
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	96,211	94,827
Accumulated Amortization	(72,021)	(70,095)
Valuation Allowance	(156)	(47)
Net Intangible Assets	24,034	24,685
Core deposits
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	101,160	101,160
Accumulated Amortization	(43,764)	(40,384)
Valuation Allowance	0	0
Net Intangible Assets	57,396	60,776
Other
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	3,945	3,945
Accumulated Amortization	(2,689)	(2,634)
Valuation Allowance	0	0
Net Intangible Assets	$ 1,256	$ 1,311