Business segment information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 29, 2013 station	Sep. 23, 2012	Sep. 29, 2013 station	Sep. 23, 2012
Segment Reporting Information [Line Items]
Number of television stations	23		23
Revenues	$ 1,252,890	$ 1,309,261	$ 3,793,324	$ 3,834,888
Operating Income (Loss)	171,698	217,199	525,637	569,375
Depreciation Amortization Of Intangible Assets And Asset Impairment And Other Charges Operating	52,146	52,736	157,318	158,438
Equity Method Investment, Ownership Percentage	18.00%		18.00%
Publishing [Member]
Segment Reporting Information [Line Items]
Revenues	858,079	890,200	2,633,543	2,684,595
Operating Income (Loss)	62,744	73,731	208,073	239,982
Depreciation Amortization Of Intangible Assets And Asset Impairment And Other Charges Operating	32,183	33,276	95,834	100,226
Broadcasting [Member]
Segment Reporting Information [Line Items]
Number of television stations	23		23
Revenues	203,364	237,039	606,906	618,593
Operating Income (Loss)	83,810	118,672	265,578	285,873
Depreciation Amortization Of Intangible Assets And Asset Impairment And Other Charges Operating	7,059	6,879	20,968	21,113
Digital [Member]
Segment Reporting Information [Line Items]
Revenues	191,447	182,022	552,875	531,700
Operating Income (Loss)	42,050	39,912	100,931	92,706
Depreciation Amortization Of Intangible Assets And Asset Impairment And Other Charges Operating	8,309	8,391	26,799	24,626
Corporate [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)	(16,906)	(15,116)	(48,945)	(49,186)
Depreciation Amortization Of Intangible Assets And Asset Impairment And Other Charges Operating	$ 4,595	$ 4,190	$ 13,717	$ 12,473