STOCK COMPENSATION PLANS (Details) (USD $)	0 Months Ended			1 Months Ended		12 Months Ended
	Jan. 13, 2014	Feb. 28, 2014	Dec. 31, 2013	May 31, 2013 Non-employee directors	Dec. 31, 2013 Restricted Stock	Dec. 31, 2013 Restricted Stock	Dec. 31, 2012 Restricted Stock	Dec. 31, 2011 Restricted Stock
Stock Compensation Plans
Number of common shares authorized under the 2003 Plan			6,500,000
Number of common shares approved for issuance				12,742
Expenses charged to other noninterest expense				$ 361,000
Number of shares available for grant under the 2003 Plan		3,927,147	1,433,647
Additional number of common shares authorized under the 2003 Plan	9,000,000
Pre-tax charge related to accelerated vesting of restricted stock					12,400,000
After tax charge related to accelerated vesting of restricted stock					12,200,000
Additional compensation and tax expense related to change in control payments that would incur at consummation of CapitalSource merger						21,000,000
Unvested restricted stock, Number of Shares
Balance at the beginning of the period (in shares)			1,216,524			1,698,281	1,675,730	1,230,582
Granted (in shares)						673,900	226,400	692,900
Shares issued by the Company upon vesting (in shares)						(819,461)	(195,871)	(203,174)
Forfeited (in shares)						(336,196)	(7,978)	(44,578)
Balance at the end of the period (in shares)			1,216,524		1,216,524	1,216,524	1,698,281	1,675,730
Unvested restricted stock, Weighted Average Fair Value On Grant Date
Balance at the beginning of the period (in dollars per share)						$ 30.68	$ 30.53	$ 35.86
Granted (in dollars per share)						$ 29.06	$ 23.77	$ 20.50
Shares issued by the Company upon vesting (in dollars per share)						$ 24.84	$ 21.69	$ 30.13
Forfeited (in dollars per share)						$ 48.92	$ 22.31	$ 23.56
Balance at the end of the period (in dollars per share)					$ 28.69	$ 28.69	$ 30.68	$ 30.53
Vesting date fair value of awards vested						$ 30,900,000	$ 4,500,000	$ 3,700,000