INCOME TAXES (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Current tax expense [Abstract]
Federal	$ 108,639	$ 127,025	$ 25,668
State	23,101	24,868	5,328
Total current tax expense	131,740	151,893	30,996
Deferred Income Tax Expense (Benefit) [Abstract]
Federal	(12,127)	(33,333)	30,356
State	(4,510)	(8,042)	5,416
Total deferred tax expense (benefit)	(16,637)	(41,375)	35,772
Total income tax expense	115,103	110,518	66,768
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate	35.00%
Income taxes at statutory rates	108,546	106,247	64,085
Increase (reduction) in income taxes resulting from: [Abstract]
Nontaxable income on loans, leases and investments, net of nondeductible expenses	(1,481)	(1,571)	(1,556)
State and local income taxes, including change in valuation allowance, net of federal income tax benefit	12,084	10,937	6,984
Tax credits	(5,166)	(4,141)	(2,735)
Other, net	1,120	(954)	(10)
Total income tax expense	115,103	110,518	66,768
Deferred Tax Assets, Net [Abstract]
Allowance for loan and lease losses	105,390	89,193
Executive separation from service agreements	10,019	9,017
State operating loss carryforwards	2,426	2,544
Unrealized loss on cash flow hedge	4,231	3,748
Other	15,771	13,273
Gross deferred tax asset	162,949	116,836
Less valuation allowance	84	85
Deferred tax assets	162,865	116,751
Accelerated depreciation	14,954	13,441
Lease financing activities	11,334	9,371
Pension	25,112	(939)
Net unrealized gains on securities included in accumulated other comprehensive loss	10,450	9,218
Net deferred loan fees and costs	3,313	3,970
Intangible assets	11,681	11,648
Gain on FDIC-assisted transactions, deferred for tax purposes	34,728	28,461
Other	3,952	4,263
Deferred tax liability	90,412	80,372
Net deferred tax assets	$ 72,453	$ 36,379
Years State Income Tax Returns Are Subject To Examination	4 years