Condensed Financial Information Of Parent Company Parent Company Information (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Cash	$ 396,486	$ 313,226
Other assets	335,045	290,744
Total assets	21,288,490	16,234,605
Subordinated debentures	436,000	433,583
Total liabilities	16,890,799	12,728,375
Stockholders' Equity Attributable to Parent Only	4,397,691	3,506,230	$ 808,898	$ 589,121
Total liabilities and stockholders' equity	21,288,490	16,234,605
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Cash	416,970	309,220
Investments In Consolidated Banking Subsidiaries	3,980,537	3,105,283
Other assets	153,991	226,321
Total assets	4,551,498	3,640,824
Subordinated debentures	133,812	133,232
Other Liabilities	19,995	1,362
Total liabilities	153,807	134,594
Stockholders' Equity Attributable to Parent Only	4,397,691	3,506,230
Total liabilities and stockholders' equity	$ 4,551,498	$ 3,640,824