Other Assets (Balances) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Other Assets [Abstract]
Cash surrender value of bank-owned life insurance	$ 378,830	$ 338,002
Federal Reserve Bank and FHLB stock	169,864	68,288
Accrued interest receivable	70,393	65,218
Prepaid expenses	35,542	33,348
Accounts receivable	29,821	19,692
Private equity investments	25,493	28,018
Derivative asset positions	20,623	27,139
Other properties held for sale	14,830	10,671
SBA/GGL servicing assets, net	4,451	4,287
Miscellaneous other assets	63,373	55,511
Total other assets	$ 813,220	$ 650,174