Goodwill and Other Intangible Assets - Other Intangible Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	$ 214,783	$ 208,255
Accumulated Amortization	(149,228)	(136,941)
Valuation Allowance	(32)	(865)
Net Intangible Assets	65,523	70,449
Loan servicing rights
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	109,678	103,150
Accumulated Amortization	(86,681)	(80,340)
Valuation Allowance	(32)	(865)
Net Intangible Assets	22,965	21,945
Core deposits
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	101,160	101,160
Accumulated Amortization	(59,590)	(53,747)
Valuation Allowance	0	0
Net Intangible Assets	41,570	47,413
Other
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	3,945	3,945
Accumulated Amortization	(2,957)	(2,854)
Valuation Allowance	0	0
Net Intangible Assets	$ 988	$ 1,091