Carrying Amounts and Accumulated Amortization Expense of Acquired Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified			1 Months Ended			12 Months Ended		12 Months Ended		12 Months Ended		12 Months Ended		12 Months Ended		12 Months Ended		12 Months Ended				12 Months Ended		12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Apr. 30, 2012 Trademarks	Dec. 31, 2012 Intangible assets amortized to cost of revenues	Dec. 31, 2011 Intangible assets amortized to cost of revenues	Dec. 31, 2012 Intangible assets amortized to cost of revenues Titles, content and technology	Dec. 31, 2011 Intangible assets amortized to cost of revenues Titles, content and technology	Dec. 31, 2012 Intangible assets amortized to cost of revenues Catalogs	Dec. 31, 2011 Intangible assets amortized to cost of revenues Catalogs	Dec. 31, 2012 Intangible assets amortized to cost of revenues ProvisionX Technology	Dec. 31, 2011 Intangible assets amortized to cost of revenues ProvisionX Technology	Dec. 31, 2012 Intangible assets amortized to cost of revenues Carrier contract and related relationships	Dec. 31, 2011 Intangible assets amortized to cost of revenues Carrier contract and related relationships	Dec. 31, 2012 Intangible assets amortized to cost of revenues Licensed content	Dec. 31, 2011 Intangible assets amortized to cost of revenues Licensed content	Dec. 31, 2012 Intangible assets amortized to cost of revenues Service provider license	Dec. 31, 2011 Intangible assets amortized to cost of revenues Service provider license	Dec. 31, 2012 Intangible assets amortized to cost of revenues Trademarks	Dec. 31, 2011 Intangible assets amortized to cost of revenues Trademarks	Dec. 31, 2012 Other intangible assets amortized to operating expenses	Dec. 31, 2011 Other intangible assets amortized to operating expenses	Dec. 31, 2012 Other intangible assets amortized to operating expenses Emux Technology	Dec. 31, 2011 Other intangible assets amortized to operating expenses Emux Technology	Dec. 31, 2012 Other intangible assets amortized to operating expenses Noncompete agreement	Dec. 31, 2011 Other intangible assets amortized to operating expenses Noncompete agreement
Finite-Lived Intangible Assets [Line Items]
Intangible assets estimated useful life			7 years			2 years		1 year		6 years		5 years		5 years		9 years		7 years				6 years		4 years
Gross Carrying Value (Including Impact of Foreign Exchange)	$ 49,002	$ 42,086		$ 42,474	$ 35,622	$ 12,781	$ 11,391	$ 1,257	$ 1,216	$ 207	$ 200	$ 19,585	$ 19,206	$ 2,952	$ 2,924	$ 467	$ 463	$ 5,225	$ 222	$ 6,528	$ 6,464	$ 1,341	$ 1,297	$ 5,187	$ 5,167
Accumulated Amortization Expense (Including Impact of Foreign Exchange)	(38,113)	(32,008)		(33,377)	(29,318)	(11,518)	(11,097)	(1,257)	(1,216)	(207)	(200)	(16,421)	(13,451)	(2,952)	(2,924)	(262)	(208)	(760)	(222)	(4,736)	(2,690)	(1,341)	(1,297)	(3,395)	(1,393)
Net Carrying Value (Including Impact of Foreign Exchange)	$ 10,889	$ 10,078		$ 9,097	$ 6,304	$ 1,263	$ 294	$ 0	$ 0	$ 0	$ 0	$ 3,164	$ 5,755	$ 0	$ 0	$ 205	$ 255	$ 4,465	$ 0	$ 1,792	$ 3,774	$ 0	$ 0	$ 1,792	$ 3,774