Goodwill, Core Deposit Intangibles and Other Intangible Assets (Carrying Amount of Intangible Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 101,652	$ 89,724
Accumulated Amortization	43,099	32,779
Net Carrying Amount	58,553	56,945
Core Deposit Intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	43,504	37,118
Accumulated Amortization	21,049	15,460
Net Carrying Amount	22,455	21,658
Mortgage Servicing Rights
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	50,467	45,744
Accumulated Amortization	18,379	15,430
Net Carrying Amount	32,088	30,314
Customer Relationship Intangible
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,177	1,177
Accumulated Amortization	857	815
Net Carrying Amount	320	362
Commercial Servicing Rights
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	6,504	5,685
Accumulated Amortization	2,814	1,074
Net Carrying Amount	$ 3,690	$ 4,611