STOCKHOLDERS' EQUITY AND EARNINGS PER SHARE (Details 5) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Unrealized gains (losses) on investment securities available-for-sale:
Net unrealized gains (losses) arising during period, before-tax amount	$ 2,867		$ (4,959)		$ 55,138		$ (39,491)
Less: reclassification adjustment for gains included in net income, before-tax amount	(2,512)	[1]	(1,084)	[1]	(6,601)	[1]	(12,006)	[1]
Net unrealized gains (losses) , before-tax amount	355		(6,043)		48,537		(51,497)
Net unrealized (losses) gains arising during the period, before-tax amount	(171)		9		(207)		38
Other comprehensive income (loss), before-tax amount	184		(6,034)		48,330		(51,459)
Unrealized gains (losses) on investment securities available-for-sale:
Net unrealized gains (losses) arising during period, tax (expense) or benefit	(1,204)		2,083		(23,158)		16,586
Less: reclassification adjustment for gains included in net income, tax (expense) or benefit	1,055	[1]	455	[1]	2,772	[1]	5,042	[1]
Net unrealized gains (losses) , tax (expense) or benefit	(149)		2,538		(20,386)		21,628
Net unrealized (losses) gains arising during the period, tax (expense) or benefit	72		(4)		87		(16)
Other comprehensive income (loss), tax (expense) or benefit	(77)		2,534		(20,299)		21,612
Unrealized gains (losses) on investment securities available-for-sale:
Net unrealized gains (losses) arising during period, net of tax amount	1,663		(2,876)		31,980		(22,905)
Less: reclassification adjustment for gains included in net income, net of tax amount	(1,457)	[1]	(629)	[1]	(3,829)	[1]	(6,964)	[1]
Net unrealized gains (losses) , net of tax amount	206		(3,505)		28,151		(29,869)
Net unrealized (losses) gains arising during the period, net of tax amount	(99)		5		(120)		22
Other comprehensive income (loss)	$ 107		$ (3,500)		$ 28,031		$ (29,847)

[1] The pretax amount is reported in net gains on sales of investment securities in the consolidated statements of income.