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Stock-Based Compensation (PSUs, RSUs and Restricted Stock) - Additional Information (Detail) - USD ($) shares in Thousands, $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2017 | Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
One-time PSU shares grant approved by board of directors |  | 897
Recognition period of unvested compensation expense |  | 3 years
Performance Stock Units (PSUs) [Member] |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Vesting period |  | 3 years
One-time PSU shares grant approved by board of directors | 500 |
Performance Stock Units (PSUs) [Member] | Minimum [Member] |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Percentage of performance stock units granted |  | 0.00%
Performance Stock Units (PSUs) [Member] | Maximum [Member] |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Percentage of performance stock units granted |  | 150.00%
Restricted Stock Units (RSUs) [Member] |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Vesting period |  | 4 years
Restricted Stock [Member] |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Vesting period |  | 1 year
Market-Based PSUs, RSUs and Restricted Stock [Member] |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Unrecognized compensation expense related to other than options |  | $ 17.2
Recognition period of unvested compensation expense |  | 2 years 10 months 24 days
Stock Options, PSUs, RSUs or Restricted Stock [Member] |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Options available for issuance under shareholders-approved equity plan |  | 1,000

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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=116856206&loc=d3e5070-113901 + Details
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- Definition Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options. + 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=116856206&loc=d3e5070-113901 + Details
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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + 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 (a)(1) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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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=116856206&loc=d3e5070-113901 + Details
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