Basis of Presentation and Significant Accounting Policies - Summary of Cumulative Effect of Changes Made to Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Accounts receivable, net	$ 207,287		$ 188,300
Other current assets	216,251		259,873
Other non-current assets	759,493		728,058
Total assets	1,183,031		1,176,231
Accounts payable	58,630		51,375
Accrued personnel costs	63,953		45,264
Other current liabilities	198,731		237,607
Deferred income taxes, net	6,764		3,339
Other non-current liabilities	261,290		307,767
Total liabilities	589,368		645,352
Retained earnings	408,963		345,302
Other stockholders' equity	184,700		185,577
Total stockholders’ equity	593,663		530,879	$ 480,021	$ 427,948
Total liabilities and stockholders’ equity	1,183,031		$ 1,176,231
Accounting Standards Update 2014-09 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Accounts receivable, net		$ 198,398
Other current assets		259,953
Other non-current assets		728,786
Total assets		1,187,137
Accounts payable		57,656
Accrued personnel costs		45,859
Other current liabilities		237,720
Deferred income taxes, net		4,153
Other non-current liabilities		308,779
Total liabilities		654,167
Retained earnings		347,393
Other stockholders' equity		185,577
Total stockholders’ equity		532,970
Total liabilities and stockholders’ equity		1,187,137
Accounting Standards Update 2014-09 [Member] | Adjustments [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Accounts receivable, net	(12,671)	10,098
Other current assets	(80)	80
Other non-current assets	(647)	728
Total assets	(13,398)	10,906
Accounts payable	(7,930)	6,281
Accrued personnel costs	(587)	595
Other current liabilities	(113)	113
Deferred income taxes, net	(1,035)	814
Other non-current liabilities	(897)	1,012
Total liabilities	(10,562)	8,815
Retained earnings	(2,836)	2,091
Total stockholders’ equity	(2,836)	2,091
Total liabilities and stockholders’ equity	$ (13,398)	$ 10,906