LOANS AND LEASES AND ALLOWANCE FOR LOAN AND LEASE LOSSES - Allowance for Loan and Lease Losses and Recorded Investment Excluding Accrued Interest in Loans (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	$ 35,533	$ 29,480
Charge-offs	(102)	(357)
Recoveries	93	222
Provision	321	0
Balance at end of period	35,845	29,345
Individually evaluated for impairment	1,376	1,199
Collectively evaluated for impairment	34,263	27,940
Loans:
Individually evaluated for impairment	39,382	32,119
Collectively evaluated for impairment	4,739,710	3,659,798
Total ending loan balances	5,463,068	3,933,715	$ 5,184,394
Purchased Credit Impaired
Allowance for Loan and Lease Losses [Roll Forward]
Balance at end of period	206	206
Loans:
Total ending loan balances	683,976	241,798	712,731
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	0	0
Charge-offs	0	0
Recoveries	0	0
Provision	0	364
Balance at end of period	0	364
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	0	364
Loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	0	0
Total ending loan balances	0	0
Unallocated \| Purchased Credit Impaired
Allowance for Loan and Lease Losses [Roll Forward]
Balance at end of period	0	0
Loans:
Total ending loan balances	0	0
Commercial \| Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	5,850	6,910
Charge-offs	0	(11)
Recoveries	0	3
Provision	196	(418)
Balance at end of period	6,046	6,484
Individually evaluated for impairment	29	749
Collectively evaluated for impairment	5,959	5,677
Loans:
Individually evaluated for impairment	4,493	8,087
Collectively evaluated for impairment	978,649	480,063
Total ending loan balances	983,961	489,229	876,999
Commercial \| Commercial and industrial \| Purchased Credit Impaired
Allowance for Loan and Lease Losses [Roll Forward]
Balance at end of period	58	58
Loans:
Total ending loan balances	819	1,079	853
Commercial \| Commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	4,252	3,840
Charge-offs	0	(259)
Recoveries	0	132
Provision	(283)	191
Balance at end of period	3,969	3,904
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	3,857	3,792
Loans:
Individually evaluated for impairment	299	373
Collectively evaluated for impairment	705,176	964,929
Total ending loan balances	713,693	975,734	727,707
Commercial \| Commercial real estate \| Purchased Credit Impaired
Allowance for Loan and Lease Losses [Roll Forward]
Balance at end of period	112	112
Loans:
Total ending loan balances	8,218	10,432	9,599
Commercial \| Multi-family
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	6,012	7,179
Charge-offs	0	0
Recoveries	0	3
Provision	472	(18)
Balance at end of period	6,484	7,164
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	6,484	7,164
Loans:
Individually evaluated for impairment	0	1,566
Collectively evaluated for impairment	1,021,097	938,487
Total ending loan balances	1,021,097	940,053	904,300
Commercial \| Multi-family \| Purchased Credit Impaired
Allowance for Loan and Lease Losses [Roll Forward]
Balance at end of period	0	0
Loans:
Total ending loan balances	0	0	0
Commercial \| SBA
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	683	335
Charge-offs	0	0
Recoveries	31	72
Provision	192	159
Balance at end of period	906	566
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	887	547
Loans:
Individually evaluated for impairment	0	9
Collectively evaluated for impairment	68,700	45,109
Total ending loan balances	71,640	48,254	57,706
Commercial \| SBA \| Purchased Credit Impaired
Allowance for Loan and Lease Losses [Roll Forward]
Balance at end of period	19	19
Loans:
Total ending loan balances	2,940	3,136	3,049
Commercial \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	1,530	846
Charge-offs	0	0
Recoveries	0	0
Provision	(10)	(151)
Balance at end of period	1,520	695
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	1,520	695
Loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	68,241	38,081
Total ending loan balances	68,241	38,081	55,289
Commercial \| Construction \| Purchased Credit Impaired
Allowance for Loan and Lease Losses [Roll Forward]
Balance at end of period	0	0
Loans:
Total ending loan balances	0	0	0
Commercial \| Lease financing
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	2,195	873
Charge-offs	(102)	(87)
Recoveries	61	0
Provision	456	409
Balance at end of period	2,610	1,195
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	2,610	1,195
Loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	212,836	102,012
Total ending loan balances	212,836	102,012	192,424
Commercial \| Lease financing \| Purchased Credit Impaired
Allowance for Loan and Lease Losses [Roll Forward]
Balance at end of period	0	0
Loans:
Total ending loan balances	0	0	$ 0
Consumer \| Single Family Residential Mortgage
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	13,854	7,192
Charge-offs	0	0
Recoveries	0	0
Provision	(584)	(232)
Balance at end of period	13,270	6,960
Individually evaluated for impairment	1,347	450
Collectively evaluated for impairment	11,906	6,493
Loans:
Individually evaluated for impairment	34,296	21,790
Collectively evaluated for impairment	1,576,150	920,193
Total ending loan balances	2,282,445	1,169,134
Consumer \| Single Family Residential Mortgage \| Purchased Credit Impaired
Allowance for Loan and Lease Losses [Roll Forward]
Balance at end of period	17	17
Loans:
Total ending loan balances	671,999	227,151
Consumer \| Other Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	1,157	2,305
Charge-offs	0	0
Recoveries	1	12
Provision	(118)	(304)
Balance at end of period	1,040	2,013
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	1,040	2,013
Loans:
Individually evaluated for impairment	294	294
Collectively evaluated for impairment	108,861	170,924
Total ending loan balances	109,155	171,218
Consumer \| Other Consumer \| Purchased Credit Impaired
Allowance for Loan and Lease Losses [Roll Forward]
Balance at end of period	0	0
Loans:
Total ending loan balances	$ 0	$ 0

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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- References

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for 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 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. 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

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

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