Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Assets [Abstract]
AFS Securities - U.S. government agency notes	$ 10,119	$ 0
Quoted Prices (Level 1) [Member]
Assets [Abstract]
AFS Securities - U.S. government agency notes	0
LHFS	0	0
MSRs	0	0
IRLCs	0	0
Best efforts forward contracts	0
Significant Other Observable Inputs (Level 2) [Member]
Assets [Abstract]
AFS Securities - U.S. government agency notes	10,119
LHFS	4,530	10,313
MSRs	0	0
IRLCs	22	162
Best efforts forward contracts	3
Significant Unobservable Inputs (Level 3) [Member]
Assets [Abstract]
AFS Securities - U.S. government agency notes	0
LHFS	0	0
MSRs	477	557
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
LHFS	0
MSRs	0	0
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	10,119
LHFS	4,530
MSRs	0	0
IRLCs	22	162
Mandatory forward contracts	13	153
Best efforts forward contracts	3
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Assets [Abstract]
AFS Securities - U.S. government agency notes	0
LHFS	0
MSRs	477	557
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	10,119
LHFS	4,530	10,307
MSRs	477	557
IRLCs	22	162
Best efforts forward contracts	3
Carrying Value [Member] \| Recurring [Member]
Assets [Abstract]
AFS Securities - U.S. government agency notes	10,119
LHFS	4,530
MSRs	477	557
IRLCs	22	162
Mandatory forward contracts	13	153
Best efforts forward contracts	3
AFS Securities - 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
LHFS [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	131
MSRs [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	(80)	66
IRLCs [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	(140)	(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	(140)	$ 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	$ 3

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

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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.

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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

+ References

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- Definition

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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- Definition

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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