Accounting Policies (Cumulative Effect of the Changes Made to the Balance Sheet for the Adoption of the New Revenue Standard) (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
ASSETS
Cash, cash equivalents and marketable securities		$ 471,930
Accounts receivable	$ 264,563	237,281	$ 234,597
Inventories	179,684	163,184	164,318
Property and equipment, net	409,980	379,096	379,096
Goodwill and intangible assets, net	258,466	243,719
Other assets	284,960	246,481
TOTAL ASSETS	1,544,530	1,741,691	1,713,416
LIABILITIES AND STOCKHOLDERS’ DEFICIT
Accounts payable	65,457	66,968	66,968
Accrued liabilities	238,431	254,381	253,418
Deferred income tax liabilities	39,899	25,087	25,353
Line of credit and long-term debt	1,016,916	1,261,075
Deferred revenue	103,696	110,158
Other long-term liabilities	81,494	82,840	95,718
Total liabilities	1,545,893	1,800,509	1,767,258
Stockholders’ Deficit:
Retained earnings	1,082,292	798,569	803,545
All other stockholders' deficit and noncontrolling interest	(1,041,468)	(857,387)
Total stockholders’ deficit	(1,363)	(58,818)	(53,842)
TOTAL LIABILITIES AND STOCKHOLDERS’ DEFICIT	1,544,530	$ 1,741,691	1,713,416
Previous U.S. GAAP (Reported)
ASSETS
Cash, cash equivalents and marketable securities			471,930
Accounts receivable	260,803		234,597
Inventories	181,830		164,318
Property and equipment, net	409,980		379,096
Goodwill and intangible assets, net	258,466		243,719
Other assets	245,276		219,756
TOTAL ASSETS	1,503,232		1,713,416
LIABILITIES AND STOCKHOLDERS’ DEFICIT
Accounts payable	65,457		66,968
Accrued liabilities	237,904		253,418
Deferred income tax liabilities	38,897		25,353
Line of credit and long-term debt	1,016,916		1,261,075
Deferred revenue	63,764		64,726
Other long-term liabilities	90,420		95,718
Total liabilities	1,513,358		1,767,258
Stockholders’ Deficit:
Retained earnings	1,073,597		803,545
All other stockholders' deficit and noncontrolling interest	(1,041,468)		(857,387)
Total stockholders’ deficit	(10,126)		(53,842)
TOTAL LIABILITIES AND STOCKHOLDERS’ DEFICIT	1,503,232		1,713,416
Accounting Standards Update 2014-09 | Attributed to the New Revenue Standard
ASSETS
Accounts receivable	3,760		2,684
Inventories	(2,146)		(1,134)
Property and equipment, net	0
Goodwill and intangible assets, net	0
Other assets	39,684		26,725
TOTAL ASSETS	41,298		28,275
LIABILITIES AND STOCKHOLDERS’ DEFICIT
Accounts payable	0
Accrued liabilities	527		963
Deferred income tax liabilities	1,002		(266)
Line of credit and long-term debt	0
Deferred revenue	39,932		45,432
Other long-term liabilities	(8,926)		(12,878)
Total liabilities	32,535		33,251
Stockholders’ Deficit:
Retained earnings	8,695		(4,976)
All other stockholders' deficit and noncontrolling interest	0
Total stockholders’ deficit	8,763		(4,976)
TOTAL LIABILITIES AND STOCKHOLDERS’ DEFICIT	$ 41,298		$ 28,275