Fair Value of Assets and Liabilities (Details 2) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2018	Dec. 31, 2017
Collateral-dependent impaired loans [Member] \| Comparability adjustments (%) [Member]
Quantitative information about unobservable inputs used in recurring and nonrecurring fair value measurements
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	$ 427	$ 982
Fair Value Measurements, Valuation Technique	Market comparable properties	Market comparable properties
Fair Value Measurements, Unobservable Inputs	Comparability adjustments (%)	Comparability adjustments (%)
Fair Value Measurements, Range	20.00%
Mortgage servicing rights [Member] \| Discount Rate [Member]
Quantitative information about unobservable inputs used in recurring and nonrecurring fair value measurements
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	$ 688	$ 1,490
Fair Value Measurements, Valuation Technique	Discounted cash flow	Discounted cash flow
Fair Value Measurements, Unobservable Inputs	Discount Rate	Discount Rate
Fair Value Measurements, Range	10.16%	9.65%
Mortgage servicing rights [Member] \| Constant prepayment rate [Member]
Quantitative information about unobservable inputs used in recurring and nonrecurring fair value measurements
Fair Value Measurements, Unobservable Inputs	Constant prepayment rate	Constant prepayment rate
Fair Value Measurements, Range	6.19%	7.51%
Mortgage servicing rights [Member] \| P&I earnings credit [Member]
Quantitative information about unobservable inputs used in recurring and nonrecurring fair value measurements
Fair Value Measurements, Unobservable Inputs	P&I earnings credit	P&I earnings credit
Fair Value Measurements, Range	2.10%	1.56%
Mortgage servicing rights [Member] \| T&I earnings credit [Member]
Quantitative information about unobservable inputs used in recurring and nonrecurring fair value measurements
Fair Value Measurements, Unobservable Inputs	T&I earnings credit	T&I earnings credit
Fair Value Measurements, Range	2.89%	2.13%
Mortgage servicing rights [Member] \| Inflation for cost of servicing [Member]
Quantitative information about unobservable inputs used in recurring and nonrecurring fair value measurements
Fair Value Measurements, Unobservable Inputs	Inflation for cost of servicing	Inflation for cost of servicing
Fair Value Measurements, Range	1.50%	1.50%

Reflects the interest rate percentage.

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- Definition

Description of the inputs and valuation technique(s) used to measure fair value.

+ References

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- Definition

Description of the unobservable inputs used in the valuation of investment assets by the entity.

+ References

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Quantitative information about unobservable inputs used in recurring and nonrecurring fair value measurements.

+ References

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- Definition

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

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