STOCKHOLDERS' EQUITY AND EARNINGS PER SHARE (Details 2) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013
Basic
Net income	$ 91,805	$ 94,097	$ 98,748	$ 100,027	$ 95,502	$ 91,900	$ 84,305	$ 74,171	$ 384,677	[1]	$ 345,878	[1]	$ 293,324	[1]
Less: Preferred stock dividends									0		0		3,428
Less: Earnings allocated to participating securities									3		506		1,682
Net income allocated to common stockholders									$ 384,674		$ 345,372		$ 288,214
Basic weighted-average common shares outstanding (in shares)	143,900	143,861	143,846	143,655	143,432	143,210	143,187	141,962	143,818		142,952		137,342
Basic EPS (in dollars per share)	$ 0.64	$ 0.65	$ 0.69	$ 0.70	$ 0.67	$ 0.64	$ 0.59	$ 0.52	$ 2.67	[1]	$ 2.42	[1]	$ 2.10	[1]
Diluted
Net income allocated to common stockholders									$ 384,674		$ 345,372		$ 288,214
Add: Convertible preferred stock dividends									0		0		3,428
Net income allocated to diluted common stockholders									$ 384,674		$ 345,372		$ 291,642
Basic weighted-average common shares outstanding (in shares)	143,900	143,861	143,846	143,655	143,432	143,210	143,187	141,962	143,818		142,952		137,342
Diluted potential common shares (in shares)									694		611		2,232
Diluted weighted-average common shares outstanding (in shares)	144,686	144,590	144,480	144,349	144,116	143,810	143,689	142,632	144,512		143,563		139,574
Diluted EPS (in dollars per share)	$ 0.63	$ 0.65	$ 0.68	$ 0.69	$ 0.66	$ 0.64	$ 0.59	$ 0.52	$ 2.66	[1]	$ 2.41	[1]	$ 2.09	[1]

[1] Prior period was restated to reflect the retrospective application of adopting the new accounting guidance related to the Company’s investments in qualified affordable housing projects Accounting Standards Update (“ASU”) 2014-01. Please see Note 9 — Investments in Qualified Affordable Housing Partnerships, Tax Credit and Other Investments, Net to the Consolidated Financial Statements for additional information.