Investments TV Food Network (Details) - Television Food Network, G.P. - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 28, 2014
Schedule of Equity Method Investments [Line Items]
Revenues, net	$ 1,160,716	$ 1,099,307	$ 1,070,671
Operating income	535,131	548,919	534,477
Net income	552,146	561,657	$ 549,058
Current assets	810,811	750,425
Non-current assets	168,547	173,185
Current liabilities	94,284	87,341
Non-current liabilities	$ 138	$ 213