Accumulated Other Comprehensive Income (Loss) (Changes in AOCI by component) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ (2,602)	$ (2,778)
OCI before reclassifications	(7,935)	1,694
Tax effect	1,658	(456)
Unrealized gains (losses), net of tax	(6,277)	1,238
Cumulative Effect of New Accounting Principle in Period of Adoption	0
Ending Balance	(8,656)	(1,540)
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
Unrealized Holding Gains (Losses) on AFS Securities [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	391	30
OCI before reclassifications	(8,057)	1,677
Tax effect	1,684	(450)
Unrealized gains (losses), net of tax	(6,373)	1,227
Ending Balance	(5,759)	1,257
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
Defined Benefit Pension Plan [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(3,223)	(2,972)
OCI before reclassifications	0	0
Tax effect	0	0
Unrealized gains (losses), net of tax	0	0
Ending Balance	(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
Gain (Loss) on Derivative Instruments [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	230	164
OCI before reclassifications	122	17
Tax effect	(26)	(6)
Unrealized gains (losses), net of tax	96	11
Ending Balance	326	175
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
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	$ (37)	$ 355

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

No definition available.

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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.

+ References

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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.

+ References

No definition available.

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

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Amount after tax and 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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