Loans Receivable - Narrative (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Dec. 31, 2017	Dec. 31, 2018	Jun. 30, 2017	Jun. 30, 2016
Financing Receivable, Recorded Investment [Line Items]
Interest income recognized on impaired loans	$ 135	$ 371	$ 313	$ 376
Loans	786,141	869,730	733,997
Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 6,650	$ 3,366	$ 3,252

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.

No definition available.

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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

The gross interest income that would have been recorded in the period on troubled debt restructurings, if the loans had been current in accordance with their original terms and had been outstanding throughout the period or since origination, if held for part of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18794-111554

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