Unrestricted Subsidiaries Unrestricted Subsidiaries (Results of Operations) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Total revenues	$ 161,253us-gaap_Revenues	$ 134,124us-gaap_Revenues
Cost of revenues	28,186us-gaap_CostOfGoodsSoldSubscription	23,388us-gaap_CostOfGoodsSoldSubscription
Gross Profit	133,067us-gaap_GrossProfit	110,736us-gaap_GrossProfit
Selling and Marketing Expense	37,590us-gaap_SellingAndMarketingExpense	32,959us-gaap_SellingAndMarketingExpense
Research and Development Expense	8,447us-gaap_ResearchAndDevelopmentExpense	7,213us-gaap_ResearchAndDevelopmentExpense
General and Administrative Expense	46,500us-gaap_GeneralAndAdministrativeExpense	28,979us-gaap_GeneralAndAdministrativeExpense
Operating Expenses	92,537us-gaap_OperatingExpenses	69,151us-gaap_OperatingExpenses
Income from operations	40,530us-gaap_OperatingIncomeLoss	41,585us-gaap_OperatingIncomeLoss
Interest expense (income), net	10,313us-gaap_InterestIncomeExpenseNet	4,948us-gaap_InterestIncomeExpenseNet
Other expense (income), net	(784)us-gaap_OtherNonoperatingIncomeExpense	(319)us-gaap_OtherNonoperatingIncomeExpense
Income (loss) before income taxes	31,001	36,956
Income Tax Expense (Benefit)	9,124us-gaap_IncomeTaxExpenseBenefit	8,191us-gaap_IncomeTaxExpenseBenefit
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	21,877us-gaap_ProfitLoss	28,765us-gaap_ProfitLoss
Unrestricted Subsidiaries [Member]
Total revenues	44,420	33,368
Cost of revenues	4,354	3,852
Gross Profit	40,066	29,516
Selling and Marketing Expense	17,662	14,958
Research and Development Expense	1,901	1,072
General and Administrative Expense	17,979	8,834
Operating Expenses	37,542	24,864
Income from operations	2,524	4,652
Interest expense (income), net	2,517	1
Other expense (income), net	243	(342)
Income (loss) before income taxes	(236)	4,993
Income Tax Expense (Benefit)	319	2,027
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ (555)	$ 2,966

Costs incurred and are directly related to generating revenues in fulfilling customer subscriptions.

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