LOANS RECEIVABLE AND ALLOWANCE FOR CREDIT LOSSES (Details 9) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	$ 261,679
Ending balance	264,959	$ 261,679
Unfunded Lending Commitments
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	12,712	11,282	$ 9,437
Provision for unfunded credit reserves	7,648	1,575	2,157
Charge-offs	0	(145)	(312)
Ending balance	20,360	12,712	11,282
CRE
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	72,977
Ending balance	81,538	72,977
C&I
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	134,598
Ending balance	134,606	134,598
Residential
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	43,856
Ending balance	39,295	43,856
Consumer
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	10,248
Ending balance	9,520	10,248
PCI Loans
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	714
Ending balance	359	714
PCI Loans | CRE
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	714
Ending balance	347	714
PCI Loans | C&I
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	0
Ending balance	9	0
PCI Loans | Residential
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	0
Ending balance	3	0
PCI Loans | Consumer
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	0
Ending balance	0	0
Loans Receivable
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	261,679	249,675	234,535
Provision for (reversal of) loan losses	6,569	47,583	20,207
Charge-offs	(24,254)	(50,618)	(17,780)
Recoveries	20,965	15,039	12,713
Net recoveries (charge-offs)	(3,289)	(35,579)	(5,067)
Ending balance	264,959	261,679	249,675
Loans Receivable | PCI Loans
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	714	2,269	0
Provision for (reversal of) loan losses	(355)	(1,032)	2,269
Charge-offs	0	(523)	0
Recoveries	0	0	0
Net recoveries (charge-offs)	0	(523)	0
Ending balance	359	714	2,269
Loans Receivable | Non-PCI loans
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	260,965	247,406	234,535
Provision for (reversal of) loan losses	6,924	48,615	17,938
Charge-offs	(24,254)	(50,095)	(17,780)
Recoveries	20,965	15,039	12,713
Net recoveries (charge-offs)	(3,289)	(35,056)	(5,067)
Ending balance	264,600	260,965	247,406
Loans Receivable | Non-PCI loans | CRE
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	72,263	70,154	72,385
Provision for (reversal of) loan losses	3,338	3,264	(3,287)
Charge-offs	(1,545)	(3,137)	(3,737)
Recoveries	7,135	1,982	4,793
Net recoveries (charge-offs)	5,590	(1,155)	1,056
Ending balance	81,191	72,263	70,154
Loans Receivable | Non-PCI loans | C&I
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	134,598	115,184	107,719
Provision for (reversal of) loan losses	11,640	49,200	11,534
Charge-offs	(20,423)	(39,984)	(8,461)
Recoveries	8,782	10,198	4,392
Net recoveries (charge-offs)	(11,641)	(29,786)	(4,069)
Ending balance	134,597	134,598	115,184
Loans Receivable | Non-PCI loans | Residential
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	43,856	50,716	49,436
Provision for (reversal of) loan losses	(7,499)	(8,167)	2,473
Charge-offs	(1,686)	(1,103)	(3,197)
Recoveries	4,621	2,410	2,004
Net recoveries (charge-offs)	2,935	1,307	(1,193)
Ending balance	39,292	43,856	50,716
Loans Receivable | Non-PCI loans | Consumer
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	10,248	11,352	4,995
Provision for (reversal of) loan losses	(555)	4,318	7,218
Charge-offs	(600)	(5,871)	(2,385)
Recoveries	427	449	1,524
Net recoveries (charge-offs)	(173)	(5,422)	(861)
Ending balance	$ 9,520	$ 10,248	$ 11,352