Business Acquisition Purchase Price Value of Shares Held In Escrow To Secure Retention of Key Employees

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Defined Contribution Plan, Employer Matching Contribution, Service Period

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Share-based Compensation Arrangement by Share-based Payment Award, Award Issuance Range

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Nonvested1

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

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Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

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Aggregate number of common shares reserved for future issuance.

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Amount of expense recognized from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments), awarded to key employees or individuals. Excludes amount related to plans that cover generally all employees (for example, but not limited to, qualified pension plans).

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Amount of commitment made to pay deferred cash remuneration.

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Amount of cost for defined contribution plan.

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Maximum amount the employee may contribute to a defined contribution plan.

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Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

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

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

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Employee Incentive and Retirement Plans - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (shares)		0	0	0
Stock-based compensation expense		$ 73,639,000	$ 75,087,000	$ 70,983,000
Grants ($ per share)		$ 0
Total intrinsic value of options exercised		$ 5,900,000	1,900,000	27,000,000.0
Total fair value of stock options vested		$ 2,800,000	$ 9,800,000	19,600,000
Total shares available for future issuance (shares)		28,308,129	24,741,976
Service period		90 days
Employer 401(k) plan match to employee's eligible earnings, percentage	4.00%
Employer maximum annual match per employee for 401(k) plan	$ 5,000
Pension Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employer 401 (k) total match expense		$ 4,500,000	$ 5,000,000.0	4,400,000
Stock issued related to acquisition
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense		$ 0	0	159,000
Stock issued related to acquisition \| Series F Convertible Preferred Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for compensation arrangement		3 years
Business acquisition, shares consideration		$ 25,000,000.0
Business acquisition, value of shares placed in third party escrow to secure retention of key employees		$ 22,100,000
Performance-based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)		373,810
Unrecognized compensation cost		$ 3,300,000
Unrecognized compensation cost expected period for recognition		1 year 8 months 12 days
Requisite service period		1 year
Stock-based compensation expense		$ 3,900,000	2,800,000	1,000,000.0
Performance-based RSUs \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PBRSU target amount (percent)		200.00%
Performance-based RSUs \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PBRSU target amount (percent)		0.00%
Equity Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost expected period for recognition		6 months
Unrecognized compensation cost		$ 800,000
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)		7,531,283
Fair value		$ 114,700,000
Unrecognized compensation cost		$ 151,000,000.0
Unrecognized compensation cost expected period for recognition		2 years 9 months 18 days
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period		6 months
Stock-based compensation expense		$ 484,000	$ 1,695,000	$ 1,605,000
Issuance of common stock in connection with employee stock purchase plan (in shares)		163,970	361,840	261,907
Total shares available for future issuance (shares)		3,123,203	2,307,400	1,739,199
Developing software
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense, capitalized amount		$ 6,300,000	$ 9,100,000	$ 9,200,000
Executive Management And Key Personnel
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash awarded					$ 18,600,000
Executive Management And Key Personnel \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awarded					$ 16,300,000
Share-based Payment Arrangement, Tranche Two [Member] \| Performance-based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for compensation arrangement		2 years