Off-Balance Sheet Arrangements, Commitments And Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Certificates and other time deposits
1 year or less	$ 822,806
More than 1 year but less than 3 years	443,810
3 years or more but less than 5 years	39,054
Total	1,305,670	$ 1,365,449
Federal Home Loan Bank advances
1 year or less	101,032
More than 1 year but less than 3 years	50,060
Total	151,092
Subordinated Debentures
1 year or less	4,563
More than 1 year but less than 3 years	3,629
3 years or more but less than 5 years	10,010
5 years or more	80,759
Total	98,961
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
1 year or less	2,194
More than 1 year but less than 3 years	3,279
3 years or more but less than 5 years	2,216
Operating Leases, Future Minimum Payments, Due Thereafter	3,728
5 years or more	3,528
Total	11,217
Contractual obligations (other than securities sold under agreements to repurchase)
1 year or less	930,595
More than 1 year but less than 3 years	500,778
3 years or more but less than 5 years	51,280
5 years or more	84,287
Total	1,566,940
Interest payments on Federal Home Loan Bank advances to be paid over future periods.	1,100
Interest included in payments for subordinated debentures	$ 41,800