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

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
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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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-Publisher FASB
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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, 2021	Mar. 31, 2020	Aug. 02, 2016	Nov. 04, 2014
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
Number of shares repurchased (in shares)	0	0
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
2014 Share 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)	$ 33.89	$ 26.31
Intrinsic value of options exercised	$ 14,000,000.0	$ 9,900,000
Unrecognized compensation cost of unvested stock options	$ 49,100,000
Weighted average period of compensation cost not yet recognized (in years)	2 years 8 months 12 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	$ 44,800,000
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)	2 months 12 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	$ 10,400,000
1997 Plan \| ESPP shares available for future issuance
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
Shares purchased under ESPP (in shares)	156,000	217,000
Weighted-average price of shares purchased (in dollars per share)	$ 59.75	$ 43.51
Unrecognized compensation cost	$ 4,400,000