Allowance for Loan and Lease Losses [Abstract]

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- Definition

Total Loans [Abstract]

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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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

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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- Definition

Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
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Loans Receivable and Allowance for Loan Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Allowance for loan losses:
Individually evaluated for impairment	$ 915	$ 546
Collectively evaluated for impairment	61,427	57,632
Total	62,342	58,178	$ 54,633	$ 51,867	$ 56,948
Total loans:
Individually evaluated for impairment	17,787	22,191
Collectively evaluated for impairment	4,944,502	4,423,824
Total	4,962,289	4,446,015
Real estate loans \| One-to-four family
Allowance for loan losses:
Individually evaluated for impairment	537	423
Collectively evaluated for impairment	14,695	19,568
Total	15,232	19,991	18,533	18,638	16,442
Total loans:
Individually evaluated for impairment	9,048	11,644
Collectively evaluated for impairment	1,821,138	1,603,356
Total	1,830,186	1,615,000
Real estate loans \| Multifamily and commercial
Allowance for loan losses:
Individually evaluated for impairment	0	28
Collectively evaluated for impairment	23,251	19,905
Total	23,251	19,933	18,029	17,390	20,352
Total loans:
Individually evaluated for impairment	2,695	3,693
Collectively evaluated for impairment	2,139,459	1,866,782
Total	2,142,154	1,870,475
Real estate loans \| Construction
Allowance for loan losses:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	7,217	5,217
Total	7,217	5,217	5,299	5,960	6,248
Total loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	261,473	233,652
Total	261,473	233,652
Commercial business loans
Allowance for loan losses:
Individually evaluated for impairment	366	80
Collectively evaluated for impairment	13,810	8,195
Total	14,176	8,275	8,480	5,721	7,094
Total loans:
Individually evaluated for impairment	2,944	4,263
Collectively evaluated for impairment	330,932	273,707
Total	333,876	277,970
Consumer loans \| Home equity loans and advances
Allowance for loan losses:
Individually evaluated for impairment	12	15
Collectively evaluated for impairment	2,446	4,561
Total	2,458	4,576	4,190	4,052	6,111
Total loans:
Individually evaluated for impairment	3,100	2,591
Collectively evaluated for impairment	390,392	445,329
Total	393,492	447,920
Consumer loans \| Other consumer loans
Allowance for loan losses:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	8	8
Total	8	8	8	11	4
Total loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	1,108	998
Total	1,108	998
Unallocated
Allowance for loan losses:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	0	178
Total	0	178	$ 94	$ 95	$ 697
Total loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	0	0
Total	$ 0	$ 0