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Stock-based Compensation (Narrative) (Details) | 9 Months Ended
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Sep. 30, 2021 USD ($)
Schedule of Share-based Compensation Arrangements [Line Items] |
ESPP employer contribution match percentage | 40.00%
ESPP maximum employee contribution percentage | 5.00%
ESPP employee contribution annual limit | $ 15,000
Stock Options [Member] |
Schedule of Share-based Compensation Arrangements [Line Items] |
Contractual term | 10 years
Years until vest | 3 years
Stock options, subject to performance or market-based vesting conditions | None
Unrecognized compensation expense | $ 18,000,000
Expected weighted average period (in years) of nonvested stock options to be recognized | 1 year 3 months 18 days
Retention Awards [Member] |
Schedule of Share-based Compensation Arrangements [Line Items] |
Years until vest | 4 years
Unrecognized compensation expense | $ 99,000,000
Expected weighted average period (in years) of nonvested stock options to be recognized | 1 year 8 months 12 days
Performance Retention Awards [Member] |
Schedule of Share-based Compensation Arrangements [Line Items] |
Requisite service period | 37 months
Contractual terms of award | We expense two-thirds of the fair value of the units that are probable of being earned based on our forecasted ROIC over the 3-year performance period, and with respect to the third year of the plan, the remaining one-third of the fair value is subject to the relative three-year OIG.
ROIC performance period | 3 years
Unrecognized compensation expense | $ 25,000,000
Expected weighted average period (in years) of nonvested stock options to be recognized | 1 year 7 months 6 days

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- Definition 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. + 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 (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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