Goodwill and other intangible assets (Details 1) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 29, 2013
Changes in the Company's net goodwill
Goodwill before accumulated impairment losses beginning balance	$ 10,096,342
Accumulated impairment losses beginning balance	(7,249,473)
Beginning Balance	2,846,869
Acquisitions and adjustments	29,237
Goodwill, Written off Related to Sale of Business Unit	(19,000)
Foreign currency exchange rate changes	2,204
Total	12,441
Goodwill before accumulated impairment losses ending balance	10,105,222
Accumulated impairment losses ending balance	(7,245,912)
Ending Balance	2,859,310
Publishing [Member]
Changes in the Company's net goodwill
Goodwill before accumulated impairment losses beginning balance	7,754,959
Accumulated impairment losses beginning balance	(7,132,817)
Beginning Balance	622,142
Acquisitions and adjustments	1,121
Goodwill, Written off Related to Sale of Business Unit	0
Foreign currency exchange rate changes	(300)
Total	821
Goodwill before accumulated impairment losses ending balance	7,752,219
Accumulated impairment losses ending balance	(7,129,256)
Ending Balance	622,963
Broadcasting [Member]
Changes in the Company's net goodwill
Goodwill before accumulated impairment losses beginning balance	1,618,602
Accumulated impairment losses beginning balance	0
Beginning Balance	1,618,602
Acquisitions and adjustments	0
Goodwill, Written off Related to Sale of Business Unit	(19,000)
Foreign currency exchange rate changes	(110)
Total	(19,110)
Goodwill before accumulated impairment losses ending balance	1,599,492
Accumulated impairment losses ending balance	0
Ending Balance	1,599,492
Digital [Member]
Changes in the Company's net goodwill
Goodwill before accumulated impairment losses beginning balance	722,781
Accumulated impairment losses beginning balance	(116,656)
Beginning Balance	606,125
Acquisitions and adjustments	28,116
Goodwill, Written off Related to Sale of Business Unit	0
Foreign currency exchange rate changes	2,614
Total	30,730
Goodwill before accumulated impairment losses ending balance	753,511
Accumulated impairment losses ending balance	(116,656)
Ending Balance	$ 636,855