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Stock-Based Compensation - Activity (Detail) - $ / shares |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Jun. 17, 2020 | Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Shares issued under equity compensation plans (in shares) |  | 584,000 | 820,000 | 2,889,000 | 2,256,000
Performance Incentive Plan |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Common stock, additional shares authorized (in shares) | 10,000,000 |  |  |  |
Stock Options |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Options granted (in shares) |  | 233,000 | 131,000 | 282,000 | 246,000
Weighted average grant-date fair value, options (in dollars per share) |  | $ 11.64 | $ 13.43 | $ 11.68 | $ 15.81
Restricted Stock Units (RSU) |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
RSUs granted (in shares) |  | 693,000 | 316,000 | 1,213,000 | 712,000
Weighted average grant-date fair value, RSUs (in dollars per share) |  | $ 21.56 | $ 28.00 | $ 21.04 | $ 31.80
Employee Stock |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Common stock, additional shares authorized (in shares) | 1,000,000 |  |  |  |

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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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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 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 (d)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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