Loans Receivable - Troubled Debt Restructuring (Details) - USD ($)	6 Months Ended	12 Months Ended
Jun. 30, 2019	Dec. 31, 2018
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

Outstanding commitments to borrowers loans classified as troubled debt restructurings.

No definition available.

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- Definition

Troubled debt restructurings.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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