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Accumulated Other Comprehensive Income (Loss) (Changes in AOCI by component) (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2018 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward] |  |  |  |
Beginning Balance |  | $ 1,971 | $ (7,685) | $ (2,602)
OCI before reclassifications | $ (6,931) | 7,115 | 11,810 |
Amounts reclassified from AOCI | 345 | 105 | 262 |
Net unrealized gains (losses) | (6,586) | 7,220 | 12,072 |
Tax effect | 1,280 | (1,493) | (2,416) |
Unrealized gains (losses), net of tax | (5,306) | 5,727 | 9,656 |
Tax Cuts and Jobs Act Reclassification to Retained Earnings |  |  |  | 223
Ending Balance |  | 7,698 | 1,971 | (7,685)
Unrealized Holding Gains (Losses) on AFS Securities [Member] |  |  |  |
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward] |  |  |  |
Beginning Balance |  | 4,612 | (5,200) | 391
OCI before reclassifications | (7,229) | 7,474 | 12,276 |
Amounts reclassified from AOCI | 0 | (71) | (6) |
Net unrealized gains (losses) | (7,229) | 7,403 | 12,270 |
Tax effect | 1,415 | (1,530) | (2,458) |
Unrealized gains (losses), net of tax | (5,814) | 5,873 | 9,812 |
Tax Cuts and Jobs Act Reclassification to Retained Earnings |  |  |  | 223
Ending Balance |  | 10,485 | 4,612 | (5,200)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] |  |  |  |
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward] |  |  |  |
Beginning Balance |  | 54 | 256 | 230
OCI before reclassifications | 33 | (121) | (256) |
Amounts reclassified from AOCI | 0 | 0 | 0 |
Net unrealized gains (losses) | 33 | (121) | (256) |
Tax effect | (7) | 25 | 54 |
Unrealized gains (losses), net of tax | 26 | (96) | (202) |
Tax Cuts and Jobs Act Reclassification to Retained Earnings |  |  |  | 0
Ending Balance |  | (42) | 54 | 256
Defined Benefit Pension Plan [Member] |  |  |  |
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward] |  |  |  |
Beginning Balance |  | (2,695) | (2,741) | (3,223)
OCI before reclassifications | 265 | (238) | (210) |
Amounts reclassified from AOCI | 345 | 176 | 268 |
Net unrealized gains (losses) | 610 | (62) | 58 |
Tax effect | (128) | 12 | (12) |
Unrealized gains (losses), net of tax | $ 482 | (50) | 46 |
Tax Cuts and Jobs Act Reclassification to Retained Earnings |  |  |  | 0
Ending Balance |  | $ (2,745) | $ (2,695) | $ (2,741)

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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e637-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669686-108580 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e681-108580 + Details
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