Accumulated Other Comprehensive Income (Loss) (Changes in AOCI by component) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance		$ (7,685)	$ (2,602)	$ (2,778)
OCI before reclassifications	$ 343	11,810	(6,931)
Amounts reclassified from AOCI	270	262	345
Net unrealized gains (losses)	613	12,072	(6,586)
Tax effect	(70)	(2,416)	1,280
Unrealized gains (losses), net of tax	543	9,656	(5,306)
Tax Cuts and Jobs Act Reclassification to Retained Earnings				(367)
Cumulative Effect of New Accounting Principle in Period of Adoption			0
Ending Balance	(2,602)	1,971	(7,685)	(2,602)
Unrealized Holding Gains (Losses) on AFS Securities [Member]
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance		(5,200)	391	30
OCI before reclassifications	289	12,276	(7,229)
Amounts reclassified from AOCI	(142)	(6)	0
Net unrealized gains (losses)	147	12,270	(7,229)
Tax effect	89	(2,458)	1,415
Unrealized gains (losses), net of tax	236	9,812	(5,814)
Tax Cuts and Jobs Act Reclassification to Retained Earnings				125
Ending Balance	391	4,612	(5,200)	391
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance		256	230	164
OCI before reclassifications	43	(256)	33
Amounts reclassified from AOCI	0	0	0
Net unrealized gains (losses)	43	(256)	33
Tax effect	(15)	54	(7)
Unrealized gains (losses), net of tax	28	(202)	26
Tax Cuts and Jobs Act Reclassification to Retained Earnings				38
Ending Balance	230	54	256	230
Defined Benefit Pension Plan [Member]
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance		(2,741)	(3,223)	(2,972)
OCI before reclassifications	11	(210)	265
Amounts reclassified from AOCI	412	268	345
Net unrealized gains (losses)	423	58	610
Tax effect	(144)	(12)	(128)
Unrealized gains (losses), net of tax	279	46	482
Tax Cuts and Jobs Act Reclassification to Retained Earnings				(530)
Ending Balance	$ (3,223)	$ (2,695)	(2,741)	$ (3,223)
AOCI Attributable to Parent [Member]
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Cumulative Effect of New Accounting Principle in Period of Adoption			223
Accounting Standards Update 2016-01
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Cumulative Effect of New Accounting Principle in Period of Adoption			223
Accounting Standards Update 2016-01 \| Unrealized Holding Gains (Losses) on AFS Securities [Member]
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Cumulative Effect of New Accounting Principle in Period of Adoption			223
Accounting Standards Update 2016-01 \| Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Cumulative Effect of New Accounting Principle in Period of Adoption			0
Accounting Standards Update 2016-01 \| Defined Benefit Pension Plan [Member]
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Cumulative Effect of New Accounting Principle in Period of Adoption			$ 0

Tax Cuts and Jobs Act, Non-cash Reclassification to Retained Earnings

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Amount before tax and reclassification adjustments of other comprehensive income (loss).

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Amount before tax, after reclassification adjustments of other comprehensive income (loss).

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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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Amount before tax of reclassification adjustments of other comprehensive income (loss).

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