Stock-Based Compensation Plans (Summary of Nonvested Stock Options) (Details) - $ / shares	12 Months Ended
Dec. 31, 2020	Dec. 31, 2018
Awards
Nonvested, beginning	1,850
Granted	0
Vested	(950)
Forfeited	0
Nonvested, ending	900
Weighted- Average Grant Date Fair Value
Nonvested, beginning	$ 6.48
Granted	0	$ 7.78
Vested	6.08
Forfeited	0
Nonvested, ending	$ 6.89

Non Union Employees [Member]

No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Number of non-vested options outstanding.

+ References

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- Definition

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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- Definition

Number of non-vested options forfeited.

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- Definition

Weighted average grant-date fair value of non-vested options forfeited.

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- Definition

Weighted average grant-date fair value of non-vested options outstanding.

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Number of options vested.

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- Definition

Weighted average grant-date fair value of options vested.

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