Stock-Based Compensation (Stock Options Narrative) (Details) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($) $ / shares
Number of Shares
Intrinsic values of options exercised	$ 1.6
Unrecognized employee stock-based compensation	$ 4.0
Weighted average grant date fair value (usd per share) \| $ / shares	$ 2.85
Fair value of options vested in period	$ 1.6
Stock Option
Number of Shares
Unrecognized employee stock-based compensation, period for recognition	2 years 7 months 6 days

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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