Other Borrowings - FHLB Advances - (Details 2) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
FHLB Advances
Outstanding advances	$ 130,000	$ 136,000
FHLB Advances
FHLB Advances
Loans pledged via a blanket lien to the FHLB for advances and letters of credit	2,600,000,000
Total borrowing capacity at FHLB	1,200,000,000
Letter of credit borrowed	8,700,000
Unused net credit available with the FHLB	$ 1,200,000,000