Federal Home Loan Bank Advances, Other Borrowings and Subordinated Notes Federal Home Loan Bank Advances, Other Borrowings and Subordinated Notes (Summary of Debt) (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Debt Disclosure [Abstract]
Federal Home Loan Bank advances	$ 444,017	$ 733,050	$ 580,582
Other borrowings:
Notes payable	75,000	0	0
Securities sold under repurchase agreements	48,295	48,566	24,633
Other	18,556	18,822	19,083
Secured borrowings	120,057	129,077	0
Total other borrowings	261,908	196,465	43,716
Subordinated notes	140,000	140,000	140,000
Total Federal Home Loan Bank advances, other borrowings and subordinated notes	$ 845,925	$ 1,069,515	$ 764,298