Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Assets [Abstract]
AFS Securities - U.S. government agency notes	$ 3,129	$ 0
U.S. Government Agency Notes [Member]
Assets [Abstract]
AFS Securities - U.S. government agency notes	3,129
Quoted Prices (Level 1) [Member]
Assets [Abstract]
AFS Securities - U.S. government agency notes	0
Loans held for sale ("LHFS")	0	0
Mortgage servicing rights ("MSRs")	0	0
Interest rate lock commitments ("IRLCs")	0	0
Best efforts forward contracts	0
Significant Other Observable Inputs (Level 2) [Member]
Assets [Abstract]
AFS Securities - U.S. government agency notes	3,129
Loans held for sale ("LHFS")	4,871	10,313
Mortgage servicing rights ("MSRs")	0	0
Interest rate lock commitments ("IRLCs")	42	162
Best efforts forward contracts	6
Significant Unobservable Inputs (Level 3) [Member]
Assets [Abstract]
AFS Securities - U.S. government agency notes	0
Loans held for sale ("LHFS")	0	0
Mortgage servicing rights ("MSRs")	473	557
Interest rate lock commitments ("IRLCs")	0	0
Best efforts forward contracts	0
Recurring [Member] \| Quoted Prices (Level 1) [Member]
Assets [Abstract]
AFS Securities - U.S. government agency notes	0
Loans held for sale ("LHFS")	0
Mortgage servicing rights ("MSRs")	0	0
Interest rate lock commitments ("IRLCs")	0	0
Mandatory forward contracts	0	0
Best efforts forward contracts	0
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Assets [Abstract]
AFS Securities - U.S. government agency notes	3,129
Loans held for sale ("LHFS")	4,871
Mortgage servicing rights ("MSRs")	0	0
Interest rate lock commitments ("IRLCs")	42	162
Mandatory forward contracts	7	153
Best efforts forward contracts	6
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Assets [Abstract]
AFS Securities - U.S. government agency notes	0
Loans held for sale ("LHFS")	0
Mortgage servicing rights ("MSRs")	473	557
Interest rate lock commitments ("IRLCs")	0	0
Mandatory forward contracts	0	0
Best efforts forward contracts	0
Carrying Value [Member]
Assets [Abstract]
AFS Securities - U.S. government agency notes	3,129
Loans held for sale ("LHFS")	4,871	10,307
Mortgage servicing rights ("MSRs")	473	557
Interest rate lock commitments ("IRLCs")	42	162
Best efforts forward contracts	6
Carrying Value [Member] \| Recurring [Member]
Assets [Abstract]
AFS Securities - U.S. government agency notes	3,129
Loans held for sale ("LHFS")	4,871
Mortgage servicing rights ("MSRs")	473	557
Interest rate lock commitments ("IRLCs")	42	162
Mandatory forward contracts	7	153
Best efforts forward contracts	6
U.S. Government Agency Notes [Member]
Fair Value Measured On Recurring Basis Gain Loss Included In Earnings Line Items [Line Items]
Total changes in fair values included in period income - assets	0
Loans Held for Sale [Member]
Fair Value Measured On Recurring Basis Gain Loss Included In Earnings Line Items [Line Items]
Total changes in fair values included in period income - assets	139
Mortgage Servicing Rights [Member]
Fair Value Measured On Recurring Basis Gain Loss Included In Earnings Line Items [Line Items]
Total changes in fair values included in period income - assets	(84)	66
Interest Rate Lock Commitments [Member]
Fair Value Measured On Recurring Basis Gain Loss Included In Earnings Line Items [Line Items]
Total changes in fair values included in period income - assets	(120)	(21)
Mandatory Forward Contracts [Member]
Fair Value Measured On Recurring Basis Gain Loss Included In Earnings Line Items [Line Items]
Total changes in fair values included in period income - assets	(146)	$ 42
Best Efforts Forward Contracts [Member]
Fair Value Measured On Recurring Basis Gain Loss Included In Earnings Line Items [Line Items]
Total changes in fair values included in period income - assets	$ 6

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

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

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

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No definition available.

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

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

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Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

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

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