Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
AFS Securities	$ 10,992	$ 11,978
U.S. Government Agency Notes [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
AFS Securities	9,004	9,997
Level 1 [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
AFS Securities	1,988	1,981
Level 2 [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
AFS Securities	9,004	9,997
Loans held for sale ("LHFS")	6,660	9,686
Level 3 [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Mortgage servicing rights ("MSRs")	400	437
Interest rate lock commitments ("IRLCs")	335	100
Carrying Value [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
AFS Securities	10,992	11,978
Loans held for sale ("LHFS")	6,660	9,686
Mortgage servicing rights ("MSRs")	400	437
Interest rate lock commitments ("IRLCs")	335	100
Recurring [Member] \| Mandatory Forward Contract Liability
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Total changes in fair values included in period income	10	(30)
Recurring [Member] \| Best Effort Forward Contracts [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Total changes in fair values included in period income	(17)	(3)
Recurring [Member] \| LHFS [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Total changes in fair values included in period income	(75)	192
Recurring [Member] \| MSRs [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Total changes in fair values included in period income	(37)	(40)
Recurring [Member] \| IRLCs [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Total changes in fair values included in period income	235	78
Recurring [Member] \| Level 1 [Member] \| U.S. Government Agency Notes [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
AFS Securities	1,988	1,981
Recurring [Member] \| Level 2 [Member] \| Mandatory Forward Contract Liability
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Mandatory forward contracts	7	16
Recurring [Member] \| Level 2 [Member] \| Best Effort Forward Contracts [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Best efforts forward contracts	16
Recurring [Member] \| Level 2 [Member] \| U.S. Government Agency Notes [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
AFS Securities	9,004	9,997
Recurring [Member] \| Level 2 [Member] \| LHFS [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Loans held for sale ("LHFS")	6,660	9,686
Recurring [Member] \| Level 3 [Member] \| MSRs [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Mortgage servicing rights ("MSRs")	400	437
Recurring [Member] \| Level 3 [Member] \| IRLCs [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Interest rate lock commitments ("IRLCs")	335	100
Recurring [Member] \| Carrying Value [Member] \| Mandatory Forward Contract Liability
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Mandatory forward contracts	7	16
Recurring [Member] \| Carrying Value [Member] \| Best Effort Forward Contracts [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Best efforts forward contracts	16
Recurring [Member] \| Carrying Value [Member] \| U.S. Government Agency Notes [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
AFS Securities	10,992	11,978
Recurring [Member] \| Carrying Value [Member] \| LHFS [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Loans held for sale ("LHFS")	6,660	9,686
Recurring [Member] \| Carrying Value [Member] \| MSRs [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Mortgage servicing rights ("MSRs")	400	437
Recurring [Member] \| Carrying Value [Member] \| IRLCs [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Interest rate lock commitments ("IRLCs")	$ 335	$ 100

The fair value disclosure of best efforts forward contracts at the end of the period.

No definition available.

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- Definition

The fair value disclosure of mandatory forward contracts at the end of the period.

+ References

No definition available.

+ Details

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- Definition

The fair value disclosure of mortgage servicing rights at the end of the period.

+ References

No definition available.

+ Details

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- Definition

The fair value disclosure of rate lock commitments at the end of the period.

+ References

No definition available.

+ Details

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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- Definition

This item represents the amount of the total realized and unrealized gains or losses for the period which are included in the statement of income (or changes in net assets); the fair value of which assets and liabilities was or is measured on a recurring basis using significant unobservable inputs (Level 3).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- References

No definition available.

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

No definition available.

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