Stock-Based Compensation - Fair Value Assumptions (Details) - PSUs	9 Months Ended
Sep. 30, 2020 $ / shares
2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	3 years
Dividend yield (%)	1.88%
Expected volatility OEC (%)	33.77%
Expected volatility peer group (%)	17.30%
Correlation	0.4574
Risk-free interest rate (%)	1.45%
Weighted average fair value of PSUs granted (in USD per share)	$ 24.89
2018 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	3 years
Dividend yield (%)	1.94%
Expected volatility OEC (%)	30.22%
Expected volatility peer group (%)	20.09%
Correlation	0.3659
Risk-free interest rate (%)	1.46%
Weighted average fair value of PSUs granted (in USD per share)	$ 39.24
2019 Plan PSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	3 years
Dividend yield (%)	4.65%
Expected volatility OEC (%)	33.30%
Expected volatility peer group (%)	17.62%
Correlation	0.5205
Risk-free interest rate (%)	1.83%
Weighted average fair value of PSUs granted (in USD per share)	$ 11.48
2020 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	3 years
Dividend yield (%)	0.00%
Expected volatility OEC (%)	60.84%
Expected volatility peer group (%)	33.22%
Correlation	0.7227
Risk-free interest rate (%)	0.14%
Weighted average fair value of PSUs granted (in USD per share)	$ 11.60

Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Correlation

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, OEC

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Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Peer Group

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

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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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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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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.

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