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Accumulated Other Comprehensive Income (Loss) (Changes in AOCI by component) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |
Beginning Balance | $ (10,167) | $ 86 | $ (2,602) | $ (2,778)
OCI before reclassifications | (2,506) | (85) | (12,388) | 4,118
Amounts reclassified from AOCI | 0 | 0 | 0 | (142)
Other Comprehensive Income (Loss), before Tax | (2,506) | (85) | (12,388) | 3,976
Tax effect | 520 | 50 | 2,614 | (1,147)
Unrealized gains (losses), net of tax | (1,986) | (35) | (9,774) | 2,829
Cumulative Effect of New Accounting Principle in Period of Adoption | 0 |  | 0 |
Ending Balance | (12,153) | 51 | (12,153) | 51
ASU 2016-01 [Member] |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption | 223 | 0 | 223 | 0
Unrealized Holding Gains (Losses) on AFS Securities [Member] |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |
Beginning Balance | (7,295) | 2,923 | 391 | 30
OCI before reclassifications | (2,513) | (96) | (12,548) | 4,151
Amounts reclassified from AOCI | 0 | 0 | 0 | (142)
Other Comprehensive Income (Loss), before Tax | (2,513) | (96) | (12,548) | 4,009
Tax effect | 522 | 54 | 2,648 | (1,158)
Unrealized gains (losses), net of tax | (1,991) | (42) | (9,900) | 2,851
Ending Balance | (9,286) | 2,881 | (9,286) | 2,881
Unrealized Holding Gains (Losses) on AFS Securities [Member] | ASU 2016-01 [Member] |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption | 223 | 0 | 223 | 0
Defined Benefit Pension Plan [Member] |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |
Beginning Balance | (3,223) | (2,972) | (3,223) | (2,972)
OCI before reclassifications | 0 | 0 | 0 | 0
Amounts reclassified from AOCI | 0 | 0 | 0 | 0
Other Comprehensive Income (Loss), before Tax | 0 | 0 | 0 | 0
Tax effect | 0 | 0 | 0 | 0
Unrealized gains (losses), net of tax | 0 | 0 | 0 | 0
Ending Balance | (3,223) | (2,972) | (3,223) | (2,972)
Defined Benefit Pension Plan [Member] | ASU 2016-01 [Member] |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption | 0 | 0 | 0 | 0
Gain (Loss) on Derivative Instruments [Member] |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |
Beginning Balance | 351 | 135 | 230 | 164
OCI before reclassifications | 7 | 11 | 160 | (33)
Amounts reclassified from AOCI | 0 | 0 | 0 | 0
Other Comprehensive Income (Loss), before Tax | 7 | 11 | 160 | (33)
Tax effect | (2) | (4) | (34) | 11
Unrealized gains (losses), net of tax | 5 | 7 | 126 | (22)
Ending Balance | 356 | 142 | 356 | 142
Gain (Loss) on Derivative Instruments [Member] | ASU 2016-01 [Member] |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption | 0 | 0 | 0 | 0
Auction Rate Money Market Preferred Stocks [Member] | Unrealized Holding Gains (Losses) on AFS Securities [Member] |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |
Unrealized gains (losses), net of tax | $ (27) | $ 63 | $ 59 | $ 604

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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=114867106&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=114867106&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=114867106&loc=d3e681-108580 + Details
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