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LOAN LOSS ALLOWANCE - Loans by Risk Rating (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 6,549,787	$ 5,725,236
Special mention
Financing Receivable, Recorded Investment [Line Items]
Loans	11,802	31,295
Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	95,302	93,109
Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans	2,616,438	2,059,767
Commercial real estate | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	287,509	253,670
Commercial real estate | Single and multi-family
Financing Receivable, Recorded Investment [Line Items]
Loans	317,491	251,606
Commercial real estate | Other
Financing Receivable, Recorded Investment [Line Items]
Loans	2,011,438	1,554,491
Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Loans	1,062,038	1,048,263
Commercial and industrial | Asset based lending
Financing Receivable, Recorded Investment [Line Items]
Loans	321,270	331,253
Commercial and industrial | Other
Financing Receivable, Recorded Investment [Line Items]
Loans	740,768	717,010
Residential mortgages
Financing Receivable, Recorded Investment [Line Items]
Loans	1,893,131	1,815,035
Residential mortgages | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	11,982	28,055
Residential mortgages | 1-4 family
Financing Receivable, Recorded Investment [Line Items]
Loans	1,881,149	1,786,980
Consumer loans
Financing Receivable, Recorded Investment [Line Items]
Loans	978,180	802,171
Consumer loans | Home equity
Financing Receivable, Recorded Investment [Line Items]
Loans	393,800	360,605
Consumer loans | Auto and other
Financing Receivable, Recorded Investment [Line Items]
Loans	584,380	441,566
Business Activities Loans
Financing Receivable, Recorded Investment [Line Items]
Loans	5,221,307	4,560,683
Business Activities Loans | Special mention
Financing Receivable, Recorded Investment [Line Items]
Loans	7,479	29,036
Business Activities Loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	51,125	60,549
Business Activities Loans | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans	1,926,344	1,634,027
Business Activities Loans | Commercial real estate | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	253,302	210,196
Business Activities Loans | Commercial real estate | Single and multi-family
Financing Receivable, Recorded Investment [Line Items]
Loans	191,819	214,823
Business Activities Loans | Commercial real estate | Real Estate
Financing Receivable, Recorded Investment [Line Items]
Loans	1,481,223	1,209,008
Business Activities Loans | Commercial real estate | Other
Financing Receivable, Recorded Investment [Line Items]
Loans	1,481,223	1,209,008
Business Activities Loans | Commercial real estate | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans	1,877,374	1,576,808
Business Activities Loans | Commercial real estate | Pass | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	253,302	208,138
Business Activities Loans | Commercial real estate | Pass | Single and multi-family
Financing Receivable, Recorded Investment [Line Items]
Loans	189,310	212,900
Business Activities Loans | Commercial real estate | Pass | Real Estate
Financing Receivable, Recorded Investment [Line Items]
Loans	1,434,762	1,155,770
Business Activities Loans | Commercial real estate | Special mention
Financing Receivable, Recorded Investment [Line Items]
Loans	6,161	3,449
Business Activities Loans | Commercial real estate | Special mention | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Business Activities Loans | Commercial real estate | Special mention | Single and multi-family
Financing Receivable, Recorded Investment [Line Items]
Loans	334	0
Business Activities Loans | Commercial real estate | Special mention | Real Estate
Financing Receivable, Recorded Investment [Line Items]
Loans	5,827	3,449
Business Activities Loans | Commercial real estate | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	42,773	53,697
Business Activities Loans | Commercial real estate | Substandard | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	0	2,058
Business Activities Loans | Commercial real estate | Substandard | Single and multi-family
Financing Receivable, Recorded Investment [Line Items]
Loans	2,175	1,923
Business Activities Loans | Commercial real estate | Substandard | Real Estate
Financing Receivable, Recorded Investment [Line Items]
Loans	40,598	49,716
Business Activities Loans | Commercial real estate | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans	36	73
Business Activities Loans | Commercial real estate | Doubtful | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Business Activities Loans | Commercial real estate | Doubtful | Single and multi-family
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Business Activities Loans | Commercial real estate | Doubtful | Real Estate
Financing Receivable, Recorded Investment [Line Items]
Loans	36	73
Business Activities Loans | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Loans	908,102	827,232
Business Activities Loans | Commercial and industrial | Asset based lending
Financing Receivable, Recorded Investment [Line Items]
Loans	321,270	331,253
Business Activities Loans | Commercial and industrial | Other
Financing Receivable, Recorded Investment [Line Items]
Loans	586,832	495,979
Business Activities Loans | Commercial and industrial | Business loans
Financing Receivable, Recorded Investment [Line Items]
Loans	908,102	827,232
Business Activities Loans | Commercial and industrial | Business loans | Asset based lending
Financing Receivable, Recorded Investment [Line Items]
Loans	321,270	331,253
Business Activities Loans | Commercial and industrial | Business loans | Other
Financing Receivable, Recorded Investment [Line Items]
Loans	586,832	495,979
Business Activities Loans | Commercial and industrial | Business loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans	890,974	786,963
Business Activities Loans | Commercial and industrial | Business loans | Pass | Asset based lending
Financing Receivable, Recorded Investment [Line Items]
Loans	321,270	331,253
Business Activities Loans | Commercial and industrial | Business loans | Pass | Other
Financing Receivable, Recorded Investment [Line Items]
Loans	569,704	455,710
Business Activities Loans | Commercial and industrial | Business loans | Special mention
Financing Receivable, Recorded Investment [Line Items]
Loans	123	24,578
Business Activities Loans | Commercial and industrial | Business loans | Special mention | Asset based lending
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Business Activities Loans | Commercial and industrial | Business loans | Special mention | Other
Financing Receivable, Recorded Investment [Line Items]
Loans	123	24,578
Business Activities Loans | Commercial and industrial | Business loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	13,825	15,691
Business Activities Loans | Commercial and industrial | Business loans | Substandard | Asset based lending
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Business Activities Loans | Commercial and industrial | Business loans | Substandard | Other
Financing Receivable, Recorded Investment [Line Items]
Loans	13,825	15,691
Business Activities Loans | Commercial and industrial | Business loans | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans	3,180	0
Business Activities Loans | Commercial and industrial | Business loans | Doubtful | Asset based lending
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Business Activities Loans | Commercial and industrial | Business loans | Doubtful | Other
Financing Receivable, Recorded Investment [Line Items]
Loans	3,180	0
Business Activities Loans | Residential mortgages
Financing Receivable, Recorded Investment [Line Items]
Loans	1,594,972	1,480,937
Business Activities Loans | Residential mortgages | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	11,178	26,704
Business Activities Loans | Residential mortgages | 1-4 family
Financing Receivable, Recorded Investment [Line Items]
Loans	1,583,794	1,454,233
Business Activities Loans | Residential mortgages | Mortgages
Financing Receivable, Recorded Investment [Line Items]
Loans	1,594,971	1,480,937
Business Activities Loans | Residential mortgages | Mortgages | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	11,178	26,704
Business Activities Loans | Residential mortgages | Mortgages | 1-4 family
Financing Receivable, Recorded Investment [Line Items]
Loans	1,583,793	1,454,233
Business Activities Loans | Residential mortgages | Mortgages | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans	1,590,091	1,475,777
Business Activities Loans | Residential mortgages | Mortgages | Pass | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	11,178	26,704
Business Activities Loans | Residential mortgages | Mortgages | Pass | 1-4 family
Financing Receivable, Recorded Investment [Line Items]
Loans	1,578,913	1,449,073
Business Activities Loans | Residential mortgages | Mortgages | Special mention
Financing Receivable, Recorded Investment [Line Items]
Loans	701	857
Business Activities Loans | Residential mortgages | Mortgages | Special mention | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Business Activities Loans | Residential mortgages | Mortgages | Special mention | 1-4 family
Financing Receivable, Recorded Investment [Line Items]
Loans	701	857
Business Activities Loans | Residential mortgages | Mortgages | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	4,179	4,303
Business Activities Loans | Residential mortgages | Mortgages | Substandard | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Business Activities Loans | Residential mortgages | Mortgages | Substandard | 1-4 family
Financing Receivable, Recorded Investment [Line Items]
Loans	4,179	4,303
Business Activities Loans | Consumer loans
Financing Receivable, Recorded Investment [Line Items]
Loans	791,889	618,487
Business Activities Loans | Consumer loans | Home equity
Financing Receivable, Recorded Investment [Line Items]
Loans	313,521	307,159
Business Activities Loans | Consumer loans | Auto and other
Financing Receivable, Recorded Investment [Line Items]
Loans	478,368	311,328
Business Activities Loans | Consumer loans | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans	788,262	616,339
Business Activities Loans | Consumer loans | Performing | Home equity
Financing Receivable, Recorded Investment [Line Items]
Loans	310,846	305,562
Business Activities Loans | Consumer loans | Performing | Auto and other
Financing Receivable, Recorded Investment [Line Items]
Loans	477,416	310,777
Business Activities Loans | Consumer loans | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans	3,627	2,148
Business Activities Loans | Consumer loans | Nonperforming | Home equity
Financing Receivable, Recorded Investment [Line Items]
Loans	2,675	1,597
Business Activities Loans | Consumer loans | Nonperforming | Auto and other
Financing Receivable, Recorded Investment [Line Items]
Loans	952	551
Acquired Loans
Financing Receivable, Recorded Investment [Line Items]
Loans	1,328,480	1,164,553
Acquired Loans | Special mention
Financing Receivable, Recorded Investment [Line Items]
Loans	4,323	2,259
Acquired Loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	44,177	32,560
Acquired Loans | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans	690,094	425,740
Acquired Loans | Commercial real estate | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	34,207	43,474
Acquired Loans | Commercial real estate | Single and multi-family
Financing Receivable, Recorded Investment [Line Items]
Loans	125,672	36,783
Acquired Loans | Commercial real estate | Real Estate
Financing Receivable, Recorded Investment [Line Items]
Loans	530,215	345,483
Acquired Loans | Commercial real estate | Other
Financing Receivable, Recorded Investment [Line Items]
Loans	530,215	345,483
Acquired Loans | Commercial real estate | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans	649,437	399,586
Acquired Loans | Commercial real estate | Pass | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	33,461	42,176
Acquired Loans | Commercial real estate | Pass | Single and multi-family
Financing Receivable, Recorded Investment [Line Items]
Loans	119,414	32,796
Acquired Loans | Commercial real estate | Pass | Real Estate
Financing Receivable, Recorded Investment [Line Items]
Loans	496,562	324,614
Acquired Loans | Commercial real estate | Special mention
Financing Receivable, Recorded Investment [Line Items]
Loans	2,529	1,007
Acquired Loans | Commercial real estate | Special mention | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Acquired Loans | Commercial real estate | Special mention | Single and multi-family
Financing Receivable, Recorded Investment [Line Items]
Loans	907	655
Acquired Loans | Commercial real estate | Special mention | Real Estate
Financing Receivable, Recorded Investment [Line Items]
Loans	1,622	352
Acquired Loans | Commercial real estate | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	38,128	25,147
Acquired Loans | Commercial real estate | Substandard | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	746	1,298
Acquired Loans | Commercial real estate | Substandard | Single and multi-family
Financing Receivable, Recorded Investment [Line Items]
Loans	5,351	3,332
Acquired Loans | Commercial real estate | Substandard | Real Estate
Financing Receivable, Recorded Investment [Line Items]
Loans	32,031	20,517
Acquired Loans | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Loans	153,936	221,031
Acquired Loans | Commercial and industrial | Asset based lending
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Acquired Loans | Commercial and industrial | Other
Financing Receivable, Recorded Investment [Line Items]
Loans	153,936	221,031
Acquired Loans | Commercial and industrial | Business loans
Financing Receivable, Recorded Investment [Line Items]
Loans	153,936	221,031
Acquired Loans | Commercial and industrial | Business loans | Asset based lending
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Acquired Loans | Commercial and industrial | Business loans | Other
Financing Receivable, Recorded Investment [Line Items]
Loans	153,936	221,031
Acquired Loans | Commercial and industrial | Business loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans	147,102	212,825
Acquired Loans | Commercial and industrial | Business loans | Pass | Asset based lending
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Acquired Loans | Commercial and industrial | Business loans | Pass | Other
Financing Receivable, Recorded Investment [Line Items]
Loans	147,102	212,825
Acquired Loans | Commercial and industrial | Business loans | Special mention
Financing Receivable, Recorded Investment [Line Items]
Loans	1,260	487
Acquired Loans | Commercial and industrial | Business loans | Special mention | Asset based lending
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Acquired Loans | Commercial and industrial | Business loans | Special mention | Other
Financing Receivable, Recorded Investment [Line Items]
Loans	1,260	487
Acquired Loans | Commercial and industrial | Business loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	5,574	7,719
Acquired Loans | Commercial and industrial | Business loans | Substandard | Asset based lending
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Acquired Loans | Commercial and industrial | Business loans | Substandard | Other
Financing Receivable, Recorded Investment [Line Items]
Loans	5,574	7,719
Acquired Loans | Residential mortgages
Financing Receivable, Recorded Investment [Line Items]
Loans	298,159	334,098
Acquired Loans | Residential mortgages | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	804	1,351
Acquired Loans | Residential mortgages | 1-4 family
Financing Receivable, Recorded Investment [Line Items]
Loans	297,355	332,747
Acquired Loans | Residential mortgages | Mortgages
Financing Receivable, Recorded Investment [Line Items]
Loans	298,159	334,098
Acquired Loans | Residential mortgages | Mortgages | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	804	1,351
Acquired Loans | Residential mortgages | Mortgages | 1-4 family
Financing Receivable, Recorded Investment [Line Items]
Loans	297,355	332,747
Acquired Loans | Residential mortgages | Mortgages | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans	295,787	330,726
Acquired Loans | Residential mortgages | Mortgages | Pass | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	804	1,351
Acquired Loans | Residential mortgages | Mortgages | Pass | 1-4 family
Financing Receivable, Recorded Investment [Line Items]
Loans	294,983	329,375
Acquired Loans | Residential mortgages | Mortgages | Special mention
Financing Receivable, Recorded Investment [Line Items]
Loans	343	311
Acquired Loans | Residential mortgages | Mortgages | Special mention | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Acquired Loans | Residential mortgages | Mortgages | Special mention | 1-4 family
Financing Receivable, Recorded Investment [Line Items]
Loans	343	311
Acquired Loans | Residential mortgages | Mortgages | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	2,029	3,061
Acquired Loans | Residential mortgages | Mortgages | Substandard | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Acquired Loans | Residential mortgages | Mortgages | Substandard | 1-4 family
Financing Receivable, Recorded Investment [Line Items]
Loans	2,029	3,061
Acquired Loans | Consumer loans
Financing Receivable, Recorded Investment [Line Items]
Loans	186,291	183,684
Acquired Loans | Consumer loans | Home equity
Financing Receivable, Recorded Investment [Line Items]
Loans	80,279	53,446
Acquired Loans | Consumer loans | Auto and other
Financing Receivable, Recorded Investment [Line Items]
Loans	106,012	130,238
Acquired Loans | Consumer loans | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans	184,879	182,064
Acquired Loans | Consumer loans | Performing | Home equity
Financing Receivable, Recorded Investment [Line Items]
Loans	79,762	52,719
Acquired Loans | Consumer loans | Performing | Auto and other
Financing Receivable, Recorded Investment [Line Items]
Loans	105,117	129,345
Acquired Loans | Consumer loans | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans	1,412	1,620
Acquired Loans | Consumer loans | Nonperforming | Home equity
Financing Receivable, Recorded Investment [Line Items]
Loans	517	727
Acquired Loans | Consumer loans | Nonperforming | Auto and other
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 895	$ 893

X

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No definition available.

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5074-111524

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