Acquisitions - Summary of Final Fair Values of Assets Acquired and Liabilities Assumed (Detail) - USD ($) $ in Thousands		6 Months Ended	12 Months Ended
	Oct. 19, 2015	Jun. 30, 2016	Dec. 31, 2015
Consideration:
Goodwill		$ 448,690	$ 449,898
PEP [Member]
Consideration:
Cash paid		621,196	621,196
Cash adjustment		(1,635)
Total consideration		619,561	621,196
Current assets		69,992	69,331
Property, plant and equipment		55,201	56,163
Intangible assets subject to amortization		240,490	240,490
Other non-current assets		1,500	1,500
Goodwill		363,116	364,450
Total assets acquired		730,299	731,934
Current liabilities		21,131	21,131
Non-current deferred tax liabilities		87,578	87,578
Other non-current liabilities		2,029	2,029
Total liabilities assumed		110,738	110,738
Net assets acquired		$ 619,561	$ 621,196
PEP [Member] | Subsequent Adjustments to Fair Value [Member]
Consideration:
Cash adjustment	$ (1,635)
Total consideration	(1,635)
Current assets	661
Property, plant and equipment	(962)
Goodwill	(1,334)
Total assets acquired	(1,635)
Net assets acquired	$ (1,635)