INCOME TAXES (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Current tax expense [Abstract]
Federal	$ 85,875	$ 108,639	$ 127,025
State	9,212	23,101	24,868
Total current tax expense	95,087	131,740	151,893
Deferred Income Tax Expense (Benefit) [Abstract]
Federal	(27,344)	(12,127)	(33,333)
State	(7,921)	(4,510)	(8,042)
Total deferred tax expense (benefit)	(35,265)	(16,637)	(41,375)
Total income tax expense	59,822	115,103	110,518
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Federal statutory rate	35.00%
Income taxes at statutory rates	67,959	108,546	106,247
Increase (reduction) in income taxes resulting from: [Abstract]
Nontaxable income on loans, leases and investments, net of nondeductible expenses	(1,309)	(1,481)	(1,571)
State and local income taxes, including change in valuation allowance, net of federal income tax benefit	839	12,084	10,937
Tax credits	(7,279)	(5,166)	(4,141)
Other, net	(388)	1,120	(954)
Total income tax expense	59,822	115,103	110,518
Income tax expense reduction, resulting from favorable outcome of state tax audits	6,449
Deferred Tax Assets, Net [Abstract]
Allowance for loan and lease losses	124,928	105,788
Pension	46,178	25,112
Executive separation from service agreements	10,123	10,019
State operating loss carryforwards	652	1,350
Unrealized loss on cash flow hedge	4,106	4,231
Other	19,465	17,638
Gross deferred tax asset	205,452	164,138
Less valuation allowance	0	73
Deferred tax assets	205,452	164,065
Accelerated depreciation	12,465	14,494
Lease financing activities	10,366	11,334
Net unrealized gains on securities included in accumulated other comprehensive loss	13,292	10,450
Net deferred loan fees and costs	3,714	3,420
Intangible assets	11,897	11,681
Gain on FDIC-assisted transactions, deferred for tax purposes	29,694	34,208
Other	5,373	5,079
Deferred tax liability	86,801	90,666
Net deferred tax assets	$ 118,651	$ 73,399
Years State Income Tax Returns Are Subject To Examination	4 years