Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	May 25, 2018
Research and Development Expense [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration obligation, expense recognized	$ 144.0
Gram Games [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration payable, total years	3 years
Contingent consideration obligation	$ 78.1	$ 49.0	$ 43.5
Business Combination, Contingent Consideration, Liability	28.5
Gram Games [Member] | Research and Development Expense [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration obligation, expense recognized	$ 57.6	5.5
Small Giant [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration payable, total years	3 years
Contingent consideration obligation	$ 242.0	$ 98.0
Small Giant [Member] | Research and Development Expense [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration obligation, expense recognized	$ 144.0