Incentive Based Compensation Plans - Stock Option Award Assumptions (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Incentive Based Compensation Plans [Abstract]
Share-based Payment Arrangement, Exercise of Option, Tax Benefit	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Exercise price per share (in dollars per share)	$ 16.79	$ 14.52	$ 15.80
Expected annual dividend yield	1.20%	1.40%	1.30%
Expected life in years	5 years 9 months 25 days	6 years 5 months 12 days	6 years 4 months 24 days
Expected volatility	43.00%	43.00%	42.00%
Risk-free interest rate	2.50%	2.80%	2.10%
Weighted average grant date fair value of stock option awards granted (in dollars per share)	$ 6.62	$ 5.83	$ 6.07

Incentive Based Compensation Plans [Abstract]

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- Definition

Amount of tax benefit from exercise of option under share-based payment arrangement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=SL79508275-113901

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ 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
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