Fair Value Measurements - Additional Information (Detail) - USD ($)	3 Months Ended			12 Months Ended
	Sep. 30, 2016	Mar. 31, 2016	Sep. 30, 2015	Dec. 31, 2016	Dec. 31, 2015
Rising Tide [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Maximum amount payable			$ 140,000,000	$ 10,200,000
Potential future payments maximum period			3 years
Contingent consideration liability					$ 18,500,000
Amount held in escrow				5,100,000
Zindagi [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Maximum amount payable		$ 60,000,000		$ 60,000,000
Potential future payments maximum period		3 years		3 years
Contingent consideration liability		$ 1,300,000		$ 200,000
PuzzleSocial [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Maximum amount payable	$ 42,000,000			$ 42,000,000
Potential future payments maximum period	2 years 6 months			2 years 6 months
Contingent consideration liability	$ 400,000			$ 700,000
Research and Development [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in fair value of contingent consideration liability				(9,100,000)	$ 6,100,000
Research and Development [Member] | Rising Tide [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in fair value of contingent consideration liability				(8,300,000)
Research and Development [Member] | Zindagi [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in fair value of contingent consideration liability				(1,100,000)
Research and Development [Member] | PuzzleSocial [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in fair value of contingent consideration liability				$ 300,000