Mortgage Servicing Rights - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended	6 Months Ended
	Jul. 01, 2017	Jun. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Servicing Assets At Fair Value [Line Items]
Mortgage servicing rights sold		$ 11,935	$ 11,935
Mortgage loans serviced		1,086,465	1,086,465
Mortgage Loans Subserviced		$ 1,065,761	$ 1,065,761	$ 3,332,903
Subsequent Event
Servicing Assets At Fair Value [Line Items]
Mortgage servicing rights portfolio hedging percentage	50.00%