Fair Value Measurements (Details 4)	6 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Information regarding the initial and ending capitalization rate of MSRs
Initial capitalization rate of additions to MSRs (as a percent)	1.02%		1.11%
Capitalization servicing rate (as a percent)	0.73%	0.89%
Capitalization servicing multiple (as a percent)	260.00%	310.00%
Weighted-average servicing fee, in basis points (as a percent)	0.29%	0.29%
Mortgage servicing rights
Significant assumptions used in estimating fair value
Weighted-average prepayment speed (CPR) (as a percent)	12.30%	9.10%
Option adjusted spread, in basis points (as a percent)	9.92%	9.77%
Weighted-average delinquency rate (as a percent)	5.40%	5.30%