Deposits (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Interest-bearing Deposit Liabilities [Abstract]
Interest bearing demand deposits	$ 4,768,313	$ 4,377,407
Money market accounts, excluding brokered deposits	7,251,093	7,042,350
Savings accounts	929,402	714,410
Time deposits, excluding brokered deposits	3,234,465	3,300,004
Brokered deposits	1,378,983	1,075,520
Total interest bearing deposits	17,562,256	16,509,691
Aggregate amount of time deposits of $250,000 or more	829,500	$ 774,300
Time Deposits, by Maturity [Abstract]
Maturing within one year	2,424,336
Between 1 — 2 years	922,828
2 — 3 years	278,722
3 — 4 years	204,813
4 — 5 years	99,288
Thereafter	22,481
Time deposits	$ 3,952,468