Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Unrealized Gains And Losses On Available-for-sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (870)	$ 121
Other comprehensive income before reclassification	1,257	(746)
Amounts reclassified from accumulated other comprehensive income	(202)	(44)
Current period other comprehensive income	1,055	(790)
Cumulative adjustment for fair value of equity securities		(201)
Ending balance	185	(870)
Defined Benefit Pension Items [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(5,510)	(6,149)
Other comprehensive income before reclassification	(1,097)	82
Amounts reclassified from accumulated other comprehensive income	436	557
Current period other comprehensive income	(661)	639
Cumulative adjustment for fair value of equity securities
Ending balance	(6,171)	(5,510)
Accumulated Other Comprehensive Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(6,380)	(6,028)
Other comprehensive income before reclassification	160	(664)
Amounts reclassified from accumulated other comprehensive income	234	513
Current period other comprehensive income	394	(151)
Cumulative adjustment for fair value of equity securities		(201)
Ending balance	$ (5,986)	$ (6,380)

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Amount after tax, before 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 stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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