Consolidated Statements of Changes in Common Shareholders' Equity (USD $) In Thousands	Total	Capital in Excess of Par Value [Member]	Retained Earnings [Member]	Cumulative Foreign Currency Translation Adjustment [Member]	Unrealized Gain on Available- for- Sale Securities [Member]	Unrealized Gain (Loss) on Pensions and Other Postretirement Plans [Member]	Cash Flow Hedge [Member]	Treasury Stock [Member]	Noncontrolling Interest [Member]	Class A Common Stock [Member]	Class B Common Stock [Member]
As of at Dec. 31, 2011		$ 252,767	$ 4,561,989	$ 21,338	$ 80,358	$ 63,625	$ 8	$ (2,398,189)	$ 0	$ 1,229	$ 18,771
Net income for the year	132,187		132,187
Acquisitions and noncontrolling interest									191
Net income attributable to noncontrolling interest	(74)		(51)						51
Net loss (income) attributable to redeemable noncontrolling interests			(23)
Distribution to noncontrolling interests									(52)
Dividends paid on common stock			(146,432)
Dividends paid on redeemable preferred stock	(895)		(895)
Repurchase of Class B common stock								(103,196)
Issuance of Class B common stock, net of restricted stock award forfeitures		(27,423)						27,038
Amortization of unearned stock compensation and stock option expense		14,662
Change in foreign currency translation adjustment (net of tax)	4,734			4,734
Change in unrealized gain on available-for-sale securities (net of taxes)	30,195				30,195
Adjustment for pensions and other postretirement plans (net of taxes)	53,544					53,544
Conversion of Class A common stock to Class B common stock										(10)	10
Taxes arising from employee stock plans		740
Cash flow hedge							(948)
As of at Dec. 31, 2012		240,746	4,546,775	26,072	110,553	117,169	(940)	(2,474,347)	190	1,219	18,781
Net income for the year	237,345		237,345
Acquisitions and noncontrolling interest		3,932
Net income attributable to noncontrolling interest	(480)		(479)						479
Net loss (income) attributable to redeemable noncontrolling interests			(1)
Distribution to noncontrolling interests									(448)
Dividends paid on redeemable preferred stock	(855)		(863)
Repurchase of Class B common stock								(17,709)
Issuance of Class B common stock, net of restricted stock award forfeitures		(4,271)						1,723
Amortization of unearned stock compensation and stock option expense		46,908
Change in foreign currency translation adjustment (net of tax)				(1,059)
Change in unrealized gain on available-for-sale securities (net of taxes)	63,110				63,110
Adjustment for pensions and other postretirement plans (net of taxes)	384,277					384,277
Conversion of Class A common stock to Class B common stock										(50)	50
Taxes arising from employee stock plans		814
Cash flow hedge							312
As of at Dec. 31, 2013	3,300,288	288,129	4,782,777	25,013	173,663	501,446	(628)	(2,490,333)	221	1,169	18,831
Net income for the year	1,293,260		1,293,260
Net income attributable to noncontrolling interest	583		(497)						497
Net loss (income) attributable to redeemable noncontrolling interests			1,080
Distribution to noncontrolling interests									(242)
Dividends paid on common stock			(67,267)
Dividends paid on redeemable preferred stock	(847)		(847)
Repurchase of Class B common stock								(1,165,427)
Issuance of Class B common stock, net of restricted stock award forfeitures		(3,186)						10,284
Amortization of unearned stock compensation and stock option expense		18,291
Change in foreign currency translation adjustment (net of tax)	(16,465)			(16,465)
Change in unrealized gain on available-for-sale securities (net of taxes)	(121,533)				(121,533)
Adjustment for pensions and other postretirement plans (net of taxes)	(108,536)					(108,536)
Conversion of Class A common stock to Class B common stock										(194)	194
Taxes arising from employee stock plans		555
Cash flow hedge							520
As of at Dec. 31, 2014	$ 3,140,775	$ 303,789	$ 6,008,506	$ 8,548	$ 52,130	$ 392,910	$ (108)	$ (3,645,476)	$ 476	$ 975	$ 19,025