Allowance for Loan and Lease Losses, Adjustments, Net [Abstract] [Roll Forward]

No definition available.

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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

No definition available.

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- References

No definition available.

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

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- Definition

Amount of direct write-downs of financing receivables charged against the allowance.

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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=84173941&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=84173941&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=82894903&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=82891408&loc=d3e4428-111522

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- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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Loans Receivable and Allowance for Loan Losses - Schedule of Allowance for Loan Losses (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Dec. 31, 2017
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 38,015	$ 37,315
Charge-offs	(689)	(843)
Recoveries	56	361
Provision for loan losses	2,117	3,050
Ending balance	39,499	39,883
Loans:
Individually evaluated for impairment			$ 34,460	$ 38,435
Collectively evaluated for impairment			6,883,709	6,702,825
Loans receivable, gross			6,944,266	6,768,175
Allowance for loan losses:
Individually evaluated for impairment			2,119	1,451
Collectively evaluated for impairment			33,510	32,537
Total Allowance for loan losses	38,015	37,315	39,499	38,015
Purchased Credit Impaired Loans
Loans:
Loans acquired with credit deterioration			26,097	26,915
Allowance for loan losses:
Loans acquired with credit deterioration			3,870	4,027
Multi-family
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	12,168	11,602
Charge-offs	0	0
Recoveries	0	0
Provision for loan losses	377	681
Ending balance	12,545	12,283
Loans:
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			3,643,539	3,500,500
Loans receivable, gross			3,645,374	3,502,381
Allowance for loan losses:
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			12,545	12,168
Total Allowance for loan losses	12,168	11,602	12,545	12,168
Multi-family \| Purchased Credit Impaired Loans
Loans:
Loans acquired with credit deterioration			1,835	1,881
Allowance for loan losses:
Loans acquired with credit deterioration			0	0
Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	10,918	11,050
Charge-offs	(50)	(198)
Recoveries	35	215
Provision for loan losses	834	1,942
Ending balance	11,737	13,009
Loans:
Individually evaluated for impairment			14,288	17,461
Collectively evaluated for impairment			1,187,632	1,130,865
Loans receivable, gross			1,202,641	1,149,090
Allowance for loan losses:
Individually evaluated for impairment			986	650
Collectively evaluated for impairment			10,300	9,804
Total Allowance for loan losses	10,918	11,050	11,737	10,918
Commercial and industrial \| Purchased Credit Impaired Loans
Loans:
Loans acquired with credit deterioration			721	764
Allowance for loan losses:
Loans acquired with credit deterioration			451	464
Commercial real estate - owner occupied
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	3,232	2,183
Charge-offs	(18)	0
Recoveries	0	0
Provision for loan losses	311	211
Ending balance	3,525	2,394
Loans:
Individually evaluated for impairment			1,483	1,448
Collectively evaluated for impairment			490,231	472,708
Loans receivable, gross			502,150	484,728
Allowance for loan losses:
Individually evaluated for impairment			764	642
Collectively evaluated for impairment			2,751	2,580
Total Allowance for loan losses	3,232	2,183	3,525	3,232
Commercial real estate - owner occupied \| Purchased Credit Impaired Loans
Loans:
Loans acquired with credit deterioration			10,436	10,572
Allowance for loan losses:
Loans acquired with credit deterioration			10	10
Commercial real estate - non-owner occupied
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	7,437	7,894
Charge-offs	0	(404)
Recoveries	0	0
Provision for loan losses	(204)	357
Ending balance	7,233	7,847
Loans:
Individually evaluated for impairment			242	160
Collectively evaluated for impairment			1,190,591	1,213,309
Loans receivable, gross			1,195,904	1,218,719
Allowance for loan losses:
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			4,512	4,630
Total Allowance for loan losses	7,437	7,894	7,233	7,437
Commercial real estate - non-owner occupied \| Purchased Credit Impaired Loans
Loans:
Loans acquired with credit deterioration			5,071	5,250
Allowance for loan losses:
Loans acquired with credit deterioration			2,721	2,807
Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	979	840
Charge-offs	0	0
Recoveries	11	81
Provision for loan losses	(69)	(36)
Ending balance	921	885
Loans:
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			81,101	85,393
Loans receivable, gross			81,101	85,393
Allowance for loan losses:
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			921	979
Total Allowance for loan losses	979	840	921	979
Construction \| Purchased Credit Impaired Loans
Loans:
Loans acquired with credit deterioration			0	0
Allowance for loan losses:
Loans acquired with credit deterioration			0	0
Residential real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,929	3,342
Charge-offs	(365)	(221)
Recoveries	7	21
Provision for loan losses	608	(62)
Ending balance	3,179	3,080
Loans:
Individually evaluated for impairment			8,242	9,247
Collectively evaluated for impairment			212,289	219,162
Loans receivable, gross			225,839	234,090
Allowance for loan losses:
Individually evaluated for impairment			365	155
Collectively evaluated for impairment			2,274	2,177
Total Allowance for loan losses	2,929	3,342	3,179	2,929
Residential real estate \| Purchased Credit Impaired Loans
Loans:
Loans acquired with credit deterioration			5,308	5,681
Allowance for loan losses:
Loans acquired with credit deterioration			540	597
Manufactured housing
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	180	286
Charge-offs	0	0
Recoveries	0	0
Provision for loan losses	(4)	(2)
Ending balance	176	284
Loans:
Individually evaluated for impairment			10,108	10,089
Collectively evaluated for impairment			75,103	77,587
Loans receivable, gross			87,687	90,227
Allowance for loan losses:
Individually evaluated for impairment			4	4
Collectively evaluated for impairment			82	82
Total Allowance for loan losses	180	286	176	180
Manufactured housing \| Purchased Credit Impaired Loans
Loans:
Loans acquired with credit deterioration			2,476	2,551
Allowance for loan losses:
Loans acquired with credit deterioration			90	94
Other
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	172	118
Charge-offs	(256)	(20)
Recoveries	3	44
Provision for loan losses	264	(41)
Ending balance	183	101
Loans:
Individually evaluated for impairment			97	30
Collectively evaluated for impairment			3,223	3,301
Loans receivable, gross			3,570	3,547
Allowance for loan losses:
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			125	117
Total Allowance for loan losses	$ 172	$ 118	183	172
Other \| Purchased Credit Impaired Loans
Loans:
Loans acquired with credit deterioration			250	216
Allowance for loan losses:
Loans acquired with credit deterioration			$ 58	$ 55