Stock-Based Compensation - Fair Value Assumptions (Details) - $ / shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Exercise Price	$ 30.06	$ 27.69	$ 24.39
PRSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued	7,198	5,550	6,089
Expected Term in Years	2 years 10 months 2 days	2 years 10 months 2 days	2 years 10 months 6 days
Correlation Coefficient Rate	79.90%	76.40%	75.90%
Volatility Rate	23.90%	22.30%	21.80%
PRSU \| Weighted Average
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-Average Risk Free Interest Rate	2.47%	2.39%	1.40%
Peer Company \| PRSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility Rate, Minimum	19.90%	19.00%	17.80%
Volatility Rate, Maximum	75.40%	51.40%	63.10%
Peer Company \| PRSU \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Correlation Coefficient Rate	34.50%	28.20%	8.20%
Peer Company \| PRSU \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Correlation Coefficient Rate	90.70%	94.30%	89.80%

Share-Based Compensation Arrangement By Share-Based Payment Award, Correlation Coefficient Rate

No definition available.

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- Definition

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

+ References

No definition available.

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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.

+ References

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- Definition

The estimated measure of the maximum 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.

+ References

No definition available.

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- Definition

The estimated measure of the minimum 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.

+ References

No definition available.

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- Definition

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

+ References

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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.

+ References

No definition available.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the 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=109197908&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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- Definition

Gross number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

+ References

No definition available.

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