FAIR VALUE MEASUREMENTS AND FAIR VALUE OF FINANCIAL INSTRUMENTS, Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Assets [Abstract]
Investment securities available-for-sale	$ 1,894,107	$ 1,802,213
Liabilities [Abstract]
Subordinated debentures		67,306
Interest Rate Swaps [Member]
Assets [Abstract]
Derivative Assets	21,624	28,252
Liabilities [Abstract]
Derivative Liabilities	21,624	28,252
Interest rate locks [Member]
Assets [Abstract]
Derivative Assets		12
Liabilities [Abstract]
Derivative Liabilities	42
Forward Sale Commitments [Member]
Liabilities [Abstract]
Derivative Liabilities	84	362
U.S. Government Agency Securities [Member]
Assets [Abstract]
Investment securities available-for-sale	990	1,023
State and Municipal Bonds [Member]
Assets [Abstract]
Investment securities available-for-sale	214,711	285,320
Agency Mortgage-backed Securities/Collateralized Mortgage Obligations [Member]
Assets [Abstract]
Investment securities available-for-sale	1,659,180	1,491,365
Non-Agency Collateralized Mortgage Obligations [Member]
Assets [Abstract]
Investment securities available-for-sale	4,258	9,110
Corporate Securities and Other [Member]
Assets [Abstract]
Investment securities available-for-sale	9,668	10,683
Equity Securities [Member]
Assets [Abstract]
Investment securities available-for-sale	5,300	4,712
Level 1 [Member]
Assets [Abstract]
Investment securities available-for-sale	4,302	3,770
Liabilities [Abstract]
Subordinated debentures		67,306
Level 1 [Member] | Interest Rate Swaps [Member]
Assets [Abstract]
Derivative Assets	0	0
Liabilities [Abstract]
Derivative Liabilities	0	0
Level 1 [Member] | Interest rate locks [Member]
Assets [Abstract]
Derivative Assets		0
Level 1 [Member] | Forward Sale Commitments [Member]
Liabilities [Abstract]
Derivative Liabilities	0	0
Level 1 [Member] | U.S. Government Agency Securities [Member]
Assets [Abstract]
Investment securities available-for-sale	0	0
Level 1 [Member] | State and Municipal Bonds [Member]
Assets [Abstract]
Investment securities available-for-sale	0	0
Level 1 [Member] | Agency Mortgage-backed Securities/Collateralized Mortgage Obligations [Member]
Assets [Abstract]
Investment securities available-for-sale	0	0
Level 1 [Member] | Non-Agency Collateralized Mortgage Obligations [Member]
Assets [Abstract]
Investment securities available-for-sale	0	0
Level 1 [Member] | Corporate Securities and Other [Member]
Assets [Abstract]
Investment securities available-for-sale	61	59
Level 1 [Member] | Equity Securities [Member]
Assets [Abstract]
Investment securities available-for-sale	4,241	3,711
Level 2 [Member]
Assets [Abstract]
Investment securities available-for-sale	1,884,061	1,795,617
Liabilities [Abstract]
Subordinated debentures		0
Level 2 [Member] | Interest Rate Swaps [Member]
Assets [Abstract]
Derivative Assets	21,624	28,252
Liabilities [Abstract]
Derivative Liabilities	21,624	28,252
Level 2 [Member] | Interest rate locks [Member]
Assets [Abstract]
Derivative Assets		12
Liabilities [Abstract]
Derivative Liabilities	42
Level 2 [Member] | Forward Sale Commitments [Member]
Liabilities [Abstract]
Derivative Liabilities	84	362
Level 2 [Member] | U.S. Government Agency Securities [Member]
Assets [Abstract]
Investment securities available-for-sale	990	1,023
Level 2 [Member] | State and Municipal Bonds [Member]
Assets [Abstract]
Investment securities available-for-sale	214,711	285,320
Level 2 [Member] | Agency Mortgage-backed Securities/Collateralized Mortgage Obligations [Member]
Assets [Abstract]
Investment securities available-for-sale	1,659,180	1,491,365
Level 2 [Member] | Non-Agency Collateralized Mortgage Obligations [Member]
Assets [Abstract]
Investment securities available-for-sale	4,258	9,110
Level 2 [Member] | Corporate Securities and Other [Member]
Assets [Abstract]
Investment securities available-for-sale	4,922	8,799
Level 2 [Member] | Equity Securities [Member]
Assets [Abstract]
Investment securities available-for-sale	0	0
Level 3 [Member]
Assets [Abstract]
Investment securities available-for-sale	5,744	2,826
Liabilities [Abstract]
Subordinated debentures		0
Level 3 [Member] | Interest Rate Swaps [Member]
Assets [Abstract]
Derivative Assets	0	0
Liabilities [Abstract]
Derivative Liabilities	0	0
Level 3 [Member] | Interest rate locks [Member]
Assets [Abstract]
Derivative Assets		0
Level 3 [Member] | Forward Sale Commitments [Member]
Liabilities [Abstract]
Derivative Liabilities	0	0
Level 3 [Member] | U.S. Government Agency Securities [Member]
Assets [Abstract]
Investment securities available-for-sale	0	0
Level 3 [Member] | State and Municipal Bonds [Member]
Assets [Abstract]
Investment securities available-for-sale	0	0
Level 3 [Member] | Agency Mortgage-backed Securities/Collateralized Mortgage Obligations [Member]
Assets [Abstract]
Investment securities available-for-sale	0	0
Level 3 [Member] | Non-Agency Collateralized Mortgage Obligations [Member]
Assets [Abstract]
Investment securities available-for-sale	0	0
Level 3 [Member] | Corporate Securities and Other [Member]
Assets [Abstract]
Investment securities available-for-sale	4,685	1,825
Level 3 [Member] | Equity Securities [Member]
Assets [Abstract]
Investment securities available-for-sale	$ 1,059	$ 1,001