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Loans Receivable - Troubled Debt Restructuring (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Financing Receivable, Modifications [Line Items]
Outstanding Commitments To Borrowers Loans Classified As Troubled Debt Restructurings	$ 0	$ 0
Troubled Debt Restructurings
Financing receivable modifications	17,000
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount	0	0.0
One-to-four family residential real estate loans - non-owner occupied loans [Member] | Non Accrual Loans [Member]
Troubled Debt Restructurings
Financing receivable modifications	$ 17,000	$ 17,000

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- Definition

Outstanding commitments to borrowers loans classified as troubled debt restructurings.

+ References

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- Definition

Troubled debt restructurings.

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
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Amount of allowance for credit losses related to recorded investment.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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