Share-Based Compensation Arrangement By Share-Based Payment Award, Non-Option Equity Instruments, Purchased

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- Definition

Share-Based Compensation Arrangements By Share-Based Payment Award, Options, Purchased In Period, Weighted Average Price

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- Definition

Share-Based Payment Arrangement, Award, Excluding Option, Cost Not Yet Recognized, Amount

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- Definition

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

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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

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

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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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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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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.

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- Definition

Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

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Employee Benefits and Share-Based Compensation - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Aug. 02, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 10,659,000	$ 8,410,000
Number of shares repurchased (in shares)	0	0
2016 and 2014 Share Repurchase Programs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining value of shares authorized for repurchase under stock repurchase programs	$ 54,900,000
The 2016 Repurchase Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Value of shares authorized for repurchase under stock repurchase programs			$ 50,000,000.0
2009 Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value of options granted (in dollars per share)	$ 26.31	$ 24.07
Intrinsic value of options exercised	$ 9,900,000	$ 17,100,000
Unrecognized compensation cost of unvested stock options	$ 46,600,000
Weighted average period of compensation cost not yet recognized (in years)	2 years 10 months 24 days
2009 Plan \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period of compensation cost not yet recognized (in years)	3 years
Unrecognized compensation cost	$ 34,100,000
2009 Plan \| RSAs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period of compensation cost not yet recognized (in years)	1 month 6 days
Unrecognized compensation cost	$ 200,000
2009 Plan \| PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period of compensation cost not yet recognized (in years)	1 year 6 months
Unrecognized compensation cost	$ 6,700,000
1997 Plan \| ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period of compensation cost not yet recognized (in years)	1 year 4 months 24 days
Shares purchased under ESPP (in shares)	217,000	210,000
Weighted-average price of shares purchased (in dollars per share)	$ 43.51	$ 40.20
Unrecognized compensation cost	$ 7,700,000