Stock-based Payments - Summary of Valuation Assumptions (Details) - $ / shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercisable (USD per share)	$ 17.85
Expected option life	3 years
Risk-free interest rate	2.40%
Historical volatility rate	27.40%
Dividend yield	0.00%
Performance-Based Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercisable (USD per share)	$ 0	$ 17.00		$ 17.00
Expected option life		1 year 1 month 6 days	1 year 2 months 12 days
Risk free interest rate, minimum		0.40%
Risk-free interest rate	0.00%
Dividend yield	0.00%	0.00%	0.00%
Risk free Interest rate, maximum			2.00%
Time-Based Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercisable (USD per share)	$ 0	$ 17.00	$ 17.00
Expected option life	0 years	6 years 4 months 24 days	5 years 6 months
Risk-free interest rate	0.00%	2.80%	2.30%
Historical volatility rate	0.00%	29.00%	26.90%
Dividend yield	0.00%	0.00%	0.00%
Minimum \| Performance-Based Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected option life	1 year
Risk-free interest rate	0.00%	1.90%	0.40%
Historical volatility rate	0.00%	22.30%	25.40%
Maximum \| Performance-Based Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected option life	2 years
Risk-free interest rate	0.00%	2.00%	1.50%
Historical volatility rate	0.00%	27.10%	29.00%

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

No definition available.

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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.

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

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No definition available.

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- Definition

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

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No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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