Impact of stock-based compensation expense on basic and diluted earnings per share.

No definition available.

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Represents the percentage of achievement of the predefined revenue and ROIC targets.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Amount, after tax, of expense for award under share-based payment arrangement.

+ References

No definition available.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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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).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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.

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No definition available.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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- Definition

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Net number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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Summary of Significant Accounting Policies - Stock-Based Compensation Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Employee Stock-Based Awards
Expiration period			3 years
Stock-based compensation	$ 12,501	$ 8,689	$ 21,020	$ 16,073
Stock-based compensation expense (income), net of tax	$ 11,649	$ 8,032	$ 19,585	$ 14,865
Stock-based compensation expense per basic and diluted share (in dollars per share)	$ 0.04	$ 0.03	$ 0.07
Employee stock-based awards, unrecognized compensation costs on nonvested awards	$ 61,833		$ 61,833
Employee stock-based awards, unrecognized compensation costs on nonvested awards, weighted average period of recognition			2 years 1 month 6 days
Stock Options
Employee Stock-Based Awards
Stock-based compensation expense per basic and diluted share (in dollars per share)				$ 0.05
Summary of Option Activity
Options outstanding balance, beginning of period (in shares)			4,271,834
Options granted (in shares)			920,706
Options exercised (in shares)			(194,480)
Options forfeited (in shares)			(12,525)
Options expired (in shares)			(15,647)
Options outstanding balance, end of period (in shares)	4,969,888		4,969,888
Options exercisable balance (in shares)	3,160,175		3,160,175
Options expected to vest (in shares)	1,704,441		1,704,441
Restricted Stock Units
Summary of Option Activity
Total fair value of shares or units vested	$ 2,375	$ 676	$ 17,710	$ 16,006
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options
Non-vested at the beginning of the period (in shares)			1,196,566
Granted (in shares)			731,801
Vested (in shares)			(527,239)
Forfeited (in shares)			(55,070)
Non-vested at the end of the period (in shares)	1,346,058		1,346,058
Performance units
Summary of Option Activity
Total fair value of shares or units vested	$ 0	$ 0	$ 6,503	$ 3,033
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options
Non-vested at the beginning of the period (in shares)			667,101
Granted (in shares)			380,856
Vested (in shares)			(169,523)
Forfeited (in shares)			(25,943)
Non-vested at the end of the period (in shares)	852,491		852,491
Performance units \| Two Thousand Seventeen
Performance Units Disclosure
Percentage of achievement of the predefined revenue and ROIC targets	100.00%		100.00%
Performance units \| Two Thousand Eighteen
Performance Units Disclosure
Percentage of achievement of the predefined revenue and ROIC targets	100.00%		100.00%
Performance units \| Two Thousand Nineteen
Performance Units Disclosure
Percentage of achievement of the predefined revenue and ROIC targets	100.00%		100.00%
Original PU Awards
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options
Non-vested at the beginning of the period (in shares)			967,049
Granted (in shares)			380,856
Vested (in shares)			(169,523)
Forfeited (in shares)			(11,093)
Non-vested at the end of the period (in shares)	1,167,289		1,167,289
PUs Adjustment
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options
Non-vested at the beginning of the period (in shares)			299,948
Granted (in shares)			0
Vested (in shares)			0
Forfeited (in shares)			(14,850)
Non-vested at the end of the period (in shares)	314,798		314,798