Supplemental Guarantor Financial Information - Consolidated Statements of Operations and Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Statement [Abstract]
Revenue	$ 272,194	$ 280,683
Cost of revenue	116,264	123,854
Gross profit	155,930	156,829
Operating expense:
Sales and marketing	67,191	66,588
Engineering and development	26,874	23,694
General and administrative	30,876	31,393
Total operating expense	124,941	121,675
Income from operations	30,989	35,154
Interest expense and other income—net	32,564	36,923
Loss before income taxes and equity earnings of unconsolidated entities	(1,575)	(1,769)
Income tax expense	669	1,719
Net loss	(2,244)	(3,488)
Equity loss of unconsolidated entities, net of tax	0	0
Net loss (income)	(2,244)	(3,488)
Comprehensive income (loss):
Foreign currency translation adjustments	(557)	(401)
Unrealized gain (loss) on cash flow hedge, net of taxes	372	(961)
Total comprehensive loss	(2,429)	(4,850)
Eliminations
Income Statement [Abstract]
Revenue	(3,949)	(3,369)
Cost of revenue	(3,949)	(3,369)
Gross profit	0	0
Operating expense:
Sales and marketing	0	0
Engineering and development	0	0
General and administrative	0	0
Total operating expense	0	0
Income from operations	0	0
Interest expense and other income—net	0	0
Loss before income taxes and equity earnings of unconsolidated entities	0	0
Income tax expense	0	0
Net loss	0	0
Equity loss of unconsolidated entities, net of tax	20,864	21,207
Net loss (income)	(20,864)	(21,207)
Comprehensive income (loss):
Foreign currency translation adjustments	0	0
Unrealized gain (loss) on cash flow hedge, net of taxes	0	0
Total comprehensive loss	(20,864)	(21,207)
Parent Company | Reportable Legal Entities
Income Statement [Abstract]
Revenue	0	0
Cost of revenue	0	0
Gross profit	0	0
Operating expense:
Sales and marketing	0	0
Engineering and development	0	0
General and administrative	482	0
Total operating expense	482	0
Income from operations	(482)	0
Interest expense and other income—net	0	0
Loss before income taxes and equity earnings of unconsolidated entities	(482)	0
Income tax expense	0	0
Net loss	(482)	0
Equity loss of unconsolidated entities, net of tax	1,762	3,488
Net loss (income)	(2,244)	(3,488)
Comprehensive income (loss):
Foreign currency translation adjustments	0	0
Unrealized gain (loss) on cash flow hedge, net of taxes	0	0
Total comprehensive loss	(2,244)	(3,488)
Subsidiary Issuer | Reportable Legal Entities
Income Statement [Abstract]
Revenue	0	0
Cost of revenue	0	0
Gross profit	0	0
Operating expense:
Sales and marketing	0	0
Engineering and development	0	0
General and administrative	61	58
Total operating expense	61	58
Income from operations	(61)	(58)
Interest expense and other income—net	32,546	37,044
Loss before income taxes and equity earnings of unconsolidated entities	(32,607)	(37,102)
Income tax expense	(7,759)	(8,830)
Net loss	(24,848)	(28,272)
Equity loss of unconsolidated entities, net of tax	(23,088)	(24,784)
Net loss (income)	(1,760)	(3,488)
Comprehensive income (loss):
Foreign currency translation adjustments	0	0
Unrealized gain (loss) on cash flow hedge, net of taxes	372	(961)
Total comprehensive loss	(1,388)	(4,449)
Guarantor Subsidiaries | Reportable Legal Entities
Income Statement [Abstract]
Revenue	260,579	268,459
Cost of revenue	108,425	117,032
Gross profit	152,154	151,427
Operating expense:
Sales and marketing	65,647	63,738
Engineering and development	23,911	21,602
General and administrative	31,160	31,051
Total operating expense	120,718	116,391
Income from operations	31,436	35,036
Interest expense and other income—net	120	14
Loss before income taxes and equity earnings of unconsolidated entities	31,316	35,022
Income tax expense	7,769	10,149
Net loss	23,547	24,873
Equity loss of unconsolidated entities, net of tax	462	89
Net loss (income)	23,085	24,784
Comprehensive income (loss):
Foreign currency translation adjustments	0	0
Unrealized gain (loss) on cash flow hedge, net of taxes	0	0
Total comprehensive loss	23,085	24,784
Non-Guarantor Subsidiaries | Reportable Legal Entities
Income Statement [Abstract]
Revenue	15,564	15,593
Cost of revenue	11,788	10,191
Gross profit	3,776	5,402
Operating expense:
Sales and marketing	1,544	2,850
Engineering and development	2,963	2,092
General and administrative	(827)	284
Total operating expense	3,680	5,226
Income from operations	96	176
Interest expense and other income—net	(102)	(135)
Loss before income taxes and equity earnings of unconsolidated entities	198	311
Income tax expense	659	400
Net loss	(461)	(89)
Equity loss of unconsolidated entities, net of tax	0	0
Net loss (income)	(461)	(89)
Comprehensive income (loss):
Foreign currency translation adjustments	(557)	(401)
Unrealized gain (loss) on cash flow hedge, net of taxes	0	0
Total comprehensive loss	$ (1,018)	$ (490)