The Company and Significant Accounting Policies - Carrying Amount of Goodwill (Detail) - USD ($)	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Goodwill [Line Items]
Goodwill, Beginning balance		$ 74,292,000
Currency		(67,000)
Impairment	$ (22,368,000)	(22,368,000)	$ 0
Goodwill, Ending balance	51,857,000	51,857,000	74,292,000
Television
Goodwill [Line Items]
Goodwill, Beginning balance		40,549,000
Goodwill, Ending balance	40,549,000	40,549,000	40,549,000
Digital
Goodwill [Line Items]
Goodwill, Beginning balance		33,743,000
Currency		(67,000)
Impairment	(22,400,000)	(22,368,000)
Goodwill, Ending balance	$ 11,308,000	$ 11,308,000	$ 33,743,000