Income Taxes (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Deferred tax assets:
Allowance for credit losses	$ 137,680	$ 129,931
Federal and state carryforwards	665
Accrued expenses	79,416	68,981
Non-accrual Interest Income	20,912	16,766
Basis difference in OREO and loans		15,118
Unrealized losses on cash flow hedges		607
Share-based compensation	28,993	26,471
Basis difference in investments	12,952	12,179
Other	3,306	3,910
Total gross deferred tax assets	283,924	273,963
Deferred tax liabilities:
Core deposit and other intangibles	11,353	5,268
State income taxes	7,763	6,625
Depreciation	6,371	2,814
Basis difference in OREO and loans	890
Deferred loan origination costs	8,483	6,728
Prepaid expenses	3,784	2,760
Unrealized gains on securities available-for-sale	62,225	53,308
Leasing activities	43,176	20,950
Basis difference in FHLB stock	13,331	19,755
Other	2,087	226
Total gross deferred tax liabilities	159,463	118,434
Net deferred tax assets	$ 124,461	$ 155,529