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Schedule of Significant Option Groups Outstanding (Detail) shares in Thousands | 12 Months Ended
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Dec. 31, 2018 $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Options Outstanding, Shares | shares | 506
Options Exercisable, Shares | shares | 256
Options Outstanding, Weighted-Average Exercise Price | $ 19.06
Options Exercisable, Weighted-Average Exercise Price | $ 8.31
$1.48 - $2.58 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Options Outstanding, Weighted-Average Remaining Contractual Life (Years) | 1 year 2 months 23 days
Options Outstanding, Shares | shares | 67
Options Exercisable, Shares | shares | 67
Range Of Exercise Prices, Lower Limit | $ 1.48
Range Of Exercise Prices, Upper Limit | 2.58
Options Outstanding, Weighted-Average Exercise Price | 1.83
Options Exercisable, Weighted-Average Exercise Price | $ 1.83
$2.67 - $3.28 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Options Outstanding, Weighted-Average Remaining Contractual Life (Years) | 2 years 2 months 12 days
Options Outstanding, Shares | shares | 103
Options Exercisable, Shares | shares | 103
Range Of Exercise Prices, Lower Limit | $ 2.67
Range Of Exercise Prices, Upper Limit | 3.28
Options Outstanding, Weighted-Average Exercise Price | 2.69
Options Exercisable, Weighted-Average Exercise Price | $ 2.69
$7.71 - $19.43 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Options Outstanding, Weighted-Average Remaining Contractual Life (Years) | 3 years 4 months 28 days
Options Outstanding, Shares | shares | 166
Options Exercisable, Shares | shares | 68
Range Of Exercise Prices, Lower Limit | $ 7.71
Range Of Exercise Prices, Upper Limit | 19.43
Options Outstanding, Weighted-Average Exercise Price | 18.59
Options Exercisable, Weighted-Average Exercise Price | $ 18.02
$28.56 - $47.70 |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Options Outstanding, Weighted-Average Remaining Contractual Life (Years) | 5 years 7 months 13 days
Options Outstanding, Shares | shares | 170
Options Exercisable, Shares | shares | 18
Range Of Exercise Prices, Lower Limit | $ 28.56
Range Of Exercise Prices, Upper Limit | 47.70
Options Outstanding, Weighted-Average Exercise Price | 36.30
Options Exercisable, Weighted-Average Exercise Price | $ 28.56

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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. + Details
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- Definition The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + 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 (g) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied. + 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)(iii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices. + 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)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + 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 (g) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding. + 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)(1)(iii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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