Condensed Financial Information Of Parent Company Parent Company Information (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Condensed Financial Statements, Captions [Line Items]
Cash	$ 419,670	$ 396,486
Other assets	319,779	335,045
Total assets	21,869,767	21,288,490
Subordinated debentures	440,744	436,000
Total liabilities	17,390,712	16,890,799
Stockholders' Equity Attributable to Parent Only	4,479,055	4,397,691	$ 3,506,230	$ 808,898
Total liabilities and stockholders' equity	21,869,767	21,288,490
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Cash	494,765	416,970
Investments In Consolidated Banking Subsidiaries	4,053,711	3,980,537
Other assets	67,074	153,991
Total assets	4,615,550	4,551,498
Subordinated debentures	134,360	133,812
Other Liabilities	2,135	19,995
Total liabilities	136,495	153,807
Stockholders' Equity Attributable to Parent Only	4,479,055	4,397,691
Total liabilities and stockholders' equity	$ 4,615,550	$ 4,551,498