Business segment information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 28, 2014	Sep. 29, 2013	Sep. 28, 2014	Sep. 29, 2013
Segment Reporting Information [Line Items]
Net Operating Revenues	$ 1,443,137	$ 1,252,890	$ 4,307,207	$ 3,793,324
Operating Income (net of depreciation, amortization and facility consolidation charges and asset impairment charges)	270,517	171,698	717,013	525,637
Depreciation, amortization and facility consolidation charges and asset impairment charges	68,196	52,146	233,619	157,318
Broadcasting [Member]
Segment Reporting Information [Line Items]
Number of television stations	46		46
Net Operating Revenues	416,509	203,364	1,197,035	606,906
Operating Income (net of depreciation, amortization and facility consolidation charges and asset impairment charges)	177,970	83,810	503,841	265,578
Depreciation, amortization and facility consolidation charges and asset impairment charges	20,307	7,059	68,122	20,968
Publishing [Member]
Segment Reporting Information [Line Items]
Net Operating Revenues	826,826	858,079	2,536,254	2,633,543
Operating Income (net of depreciation, amortization and facility consolidation charges and asset impairment charges)	62,424	62,744	158,651	208,073
Depreciation, amortization and facility consolidation charges and asset impairment charges	33,040	32,183	122,754	95,834
Digital [Member]
Segment Reporting Information [Line Items]
Net Operating Revenues	199,802	191,447	573,918	552,875
Operating Income (net of depreciation, amortization and facility consolidation charges and asset impairment charges)	48,342	42,050	107,861	100,931
Depreciation, amortization and facility consolidation charges and asset impairment charges	9,886	8,309	27,777	26,799
Corporate [Member]
Segment Reporting Information [Line Items]
Operating Income (net of depreciation, amortization and facility consolidation charges and asset impairment charges)	(18,219)	(16,906)	(53,340)	(48,945)
Depreciation, amortization and facility consolidation charges and asset impairment charges	$ 4,963	$ 4,595	$ 14,966	$ 13,717