Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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 gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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The cash outflow associated with other payments to acquire businesses including deposit on pending acquisitions and preacquisition costs.

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The cash outflow for a borrowing supported by a written promise to pay an obligation.

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Fair Value Measurements - Narrative (Details) - USD ($)	12 Months Ended
Fair Value Measurements - Narrative (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Oct. 10, 2018	Oct. 13, 2017	Jun. 10, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Outstanding note paid down	$ 400,000	$ 0	$ 0
Changes in fair value of contingent consideration	(80,000)	6,318,000	$ 18,944,000
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Gain (loss) recognized in earnings from change in the fair value of contingent consideration	80,000	(6,318,000)
Contingent consideration payments	37,645,000	23,545,000
Fiscal 2019 Acquisitions
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes payable		5,500,000
Outstanding note paid down		5,100,000
Humble Bundle
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
High-end of potential contingent consideration					$ 40,000,000.0
Contingent consideration	0	20,000,000.0
Contingent consideration payments	20,000,000.0	20,000,000.0
Ekahau Inc.
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
High-end of potential contingent consideration				$ 15,000,000.0
Contingent consideration	0	9,100,000
Contingent consideration payments	9,100,000
Other Business Acquisitions
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
High-end of potential contingent consideration	23,300,000
Contingent consideration	9,100,000	8,800,000
Contingent consideration payments	8,600,000
3.25% Convertible Notes \| Convertible Debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 593,100,000	$ 583,600,000
Stated interest rate						3.25%