LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES (Details 7) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	$ 261,679
(Reversal of) provision for loan losses	4,987		6,933
Ending balance	257,738
Ending balance allocated to:
Ending balance	257,738
Loans Receivable
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	261,679	[1]	249,675
(Reversal of) provision for loan losses	4,987		6,933
Provision allocation for unfunded loan commitments and letters of credit	(2,920)		(215)
Charge-offs	(8,800)		(6,136)
Recoveries	2,792		1,879
Net recoveries (charge-offs)	(6,008)		(4,257)
Ending balance	257,738	[1]	252,136
Ending balance allocated to:
Individually evaluated for impairment	20,173		26,718
Collectively evaluated for impairment	236,922		223,216
Acquired with deteriorated credit quality	643		2,202
Ending balance	257,738	[1]	252,136
Loans Receivable | Non-PCI loans
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	260,965		247,406
(Reversal of) provision for loan losses	5,058		7,000
Provision allocation for unfunded loan commitments and letters of credit	(2,920)		(215)
Charge-offs	(8,800)		(6,136)
Recoveries	2,792		1,879
Net recoveries (charge-offs)	(6,008)		(4,257)
Ending balance	257,095		249,934
Ending balance allocated to:
Individually evaluated for impairment	20,173		26,718
Collectively evaluated for impairment	236,922		223,216
Ending balance	257,095		249,934
Loans Receivable | PCI loans
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	714	[1]	2,269
(Reversal of) provision for loan losses	(71)		(67)
Ending balance	643	[1]	2,202
Ending balance allocated to:
Acquired with deteriorated credit quality	643		2,202
Ending balance	643	[1]	2,202
CRE | Loans Receivable | Non-PCI loans
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	72,263		70,154
(Reversal of) provision for loan losses	(2,333)		(7,036)
Charge-offs	(1,002)		(319)
Recoveries	812		828
Net recoveries (charge-offs)	(190)		509
Ending balance	69,740		63,627
Ending balance allocated to:
Individually evaluated for impairment	1,574		8,375
Collectively evaluated for impairment	68,166		55,252
Ending balance	69,740		63,627
C&I | Loans Receivable | Non-PCI loans
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	134,598		115,184
(Reversal of) provision for loan losses	5,378		16,592
Charge-offs	(6,589)		(5,531)
Recoveries	527		911
Net recoveries (charge-offs)	(6,062)		(4,620)
Ending balance	133,914		127,156
Ending balance allocated to:
Individually evaluated for impairment	17,906		16,490
Collectively evaluated for impairment	116,008		110,666
Ending balance	133,914		127,156
Residential | Loans Receivable | Non-PCI loans
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	43,856		50,716
(Reversal of) provision for loan losses	(1,571)		(2,575)
Charge-offs	(746)		(283)
Recoveries	1,451		137
Net recoveries (charge-offs)	705		(146)
Ending balance	42,990		47,995
Ending balance allocated to:
Individually evaluated for impairment	692		1,853
Collectively evaluated for impairment	42,298		46,142
Ending balance	42,990		47,995
Consumer | Loans Receivable | Non-PCI loans
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	10,248		11,352
(Reversal of) provision for loan losses	664		(196)
Charge-offs	(463)		(3)
Recoveries	2		3
Net recoveries (charge-offs)	(461)
Ending balance	10,451		11,156
Ending balance allocated to:
Individually evaluated for impairment	1
Collectively evaluated for impairment	10,450		11,156
Ending balance	10,451		11,156
Unallocated | Loans Receivable | Non-PCI loans
Financing Receivable Allowance for Credit Losses Roll Forward
(Reversal of) provision for loan losses	2,920		215
Provision allocation for unfunded loan commitments and letters of credit	$ (2,920)		$ (215)

[1] Loans net of ASC 310-30 discount.