LOANS - Loan Delinquency, including Nonaccrual Loans (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	$ 10,783	$ 13,724
60 - 89 days past due	3,853	5,591
> 90 days past due	19,742	27,862
Total Past due	34,378	47,177
Current	4,415,594	3,458,464
Total loans, excluding covered loans	4,449,972	3,505,641
> 90 days past due and still accruing	249	218
Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	2,063	2,016
60 - 89 days past due	333	161
> 90 days past due	1,727	7,136
Total Past due	4,123	9,313
Current	1,300,659	1,026,355
Total loans, excluding covered loans	1,304,782	1,035,668
> 90 days past due and still accruing	0	0
Real estate-construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	0	0
60 - 89 days past due	0	0
> 90 days past due	223	223
Total Past due	223	223
Current	193,553	80,518
Total loans, excluding covered loans	193,776	80,741
> 90 days past due and still accruing	0	0
Real estate-commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	5,697	7,800
60 - 89 days past due	2,359	4,269
> 90 days past due	12,144	12,732
Total Past due	20,200	24,801
Current	1,931,855	1,472,186
Total loans, excluding covered loans	1,952,055	1,496,987
> 90 days past due and still accruing	0	0
Real estate - residential
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	1,384	2,030
60 - 89 days past due	311	685
> 90 days past due	4,225	5,526
Total Past due	5,920	8,241
Current	420,638	344,690
Total loans, excluding covered loans	426,558	352,931
> 90 days past due and still accruing	0	0
Installment
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	106	213
60 - 89 days past due	82	40
> 90 days past due	223	379
Total Past due	411	632
Current	47,150	46,501
Total loans, excluding covered loans	47,561	47,133
> 90 days past due and still accruing	0	0
Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	1,043	985
60 - 89 days past due	553	292
> 90 days past due	951	1,648
Total Past due	2,547	2,925
Current	413,552	373,529
Total loans, excluding covered loans	416,099	376,454
> 90 days past due and still accruing	0	0
All other
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	490	680
60 - 89 days past due	215	144
> 90 days past due	249	218
Total Past due	954	1,042
Current	108,187	114,685
Total loans, excluding covered loans	109,141	115,727
> 90 days past due and still accruing	249	218
Non Covered Loans | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans, excluding covered loans	1,304,782	1,035,668
Non Covered Loans | Real estate-construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans, excluding covered loans	193,776	80,741
Non Covered Loans | Real estate-commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans, excluding covered loans	1,952,055	1,496,987
Non Covered Loans | Real estate - residential
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans, excluding covered loans	426,558	352,931
Non Covered Loans | Installment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans, excluding covered loans	47,561	47,133
Non Covered Loans | Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans, excluding covered loans	416,099	376,454
Non Covered Loans | All other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans, excluding covered loans	$ 109,141	$ 115,727