Goodwill and other intangible assets - Goodwill, Indefinite-Lived Intangible Assets, and Amortizable Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 28, 2014	Dec. 29, 2013
Goodwill and Intangible Assets Disclosure [Line Items]
Goodwill	$ 3,919,726	$ 3,914,771	$ 3,172,585
Total intangible assets, gross	7,205,495	7,206,622
Intangible assets, accumulated amortization	(220,662)	(114,273)
Total intangible assets, net	6,984,833	7,092,349
Customer relationships
Goodwill and Intangible Assets Disclosure [Line Items]
Finite-Lived Intangible Assets, Gross	903,652	904,916
Finite-Lived Intangible Assets, Accumulated Amortization	(145,398)	(71,719)
Finite-Lived Intangible Assets, Net	758,254	833,197
Other
Goodwill and Intangible Assets Disclosure [Line Items]
Finite-Lived Intangible Assets, Gross	265,148	268,578
Finite-Lived Intangible Assets, Accumulated Amortization	(75,264)	(42,554)
Finite-Lived Intangible Assets, Net	189,884	226,024
Television station FCC licenses
Goodwill and Intangible Assets Disclosure [Line Items]
Indefinite-Lived Intangible Assets (Excluding Goodwill)	1,191,950	1,191,950
Intangible assets, accumulated amortization	0	0
Trade names
Goodwill and Intangible Assets Disclosure [Line Items]
Indefinite-Lived Intangible Assets (Excluding Goodwill)	925,019	926,407
Intangible assets, accumulated amortization	0	0
Goodwill
Goodwill and Intangible Assets Disclosure [Line Items]
Goodwill	3,919,726	3,914,771
Intangible assets, accumulated amortization	$ 0	$ 0