Premises and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Premises and equipment
Premises and equipment, gross	$ 201,112	$ 202,836
Less: accumulated depreciation and amortization	145,616	142,530
Total	55,496	60,306
Depreciation and amortization expense	16,300	19,200	$ 21,000
Reduction in premises and equipment costs	4,000
Reduction in accumulated depreciation and amortization	2,800
Furniture, fixtures and equipment
Premises and equipment
Premises and equipment, gross	154,202	152,885
Leasehold improvements
Premises and equipment
Premises and equipment, gross	$ 46,910	$ 49,951