Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current Assets
Cash and cash equivalents	$ 413,991	$ 200,165
Restricted cash	9,063	13,879
Investments in marketable equity securities and other investments	587,582	599,967
Accounts receivable, net	537,156	624,216
Inventories and contracts in progress	120,622	120,834
Prepaid expenses	75,523	92,289
Income taxes receivable	29,313	10,735
Other current assets	942	1,400
Total Current Assets	1,774,192	1,663,485
Property, Plant and Equipment, Net	378,286	384,670
Lease Right-of-Use Assets	462,560	526,417
Investments in Affiliates	155,777	162,249
Goodwill, Net	1,484,750	1,388,279
Indefinite-Lived Intangible Assets	120,437	140,197
Amortized Intangible Assets, Net	204,646	233,481
Prepaid Pension Cost	1,708,305	1,292,350
Deferred Income Taxes	8,396	11,629
Deferred Charges and Other Assets	146,770	128,479
Total Assets	6,444,119	5,931,236
Current Liabilities
Accounts payable and accrued liabilities	520,236	507,701
Deferred revenue	331,021	355,156
Income taxes payable	5,140	4,121
Current portion of lease liabilities	86,797	92,714
Current portion of long-term debt	6,452	82,179
Total Current Liabilities	949,646	1,041,871
Accrued Compensation and Related Benefits	201,918	193,836
Other Liabilities	48,768	27,223
Deferred Income Taxes	521,274	427,372
Mandatorily Redeemable Noncontrolling Interest	9,240	829
Lease Liabilities	428,849	477,004
Long-Term Debt	506,103	430,650
Total Liabilities	2,665,798	2,598,785
Commitments and Contingencies (Note 18)
Redeemable Noncontrolling Interests	11,928	5,655
Preferred Stock, $1 par value; 977,000 shares authorized, none issued	0	0
Common Stockholders’ Equity
Capital in excess of par value	388,159	381,669
Retained earnings	6,804,822	6,534,427
Accumulated other comprehensive income, net of taxes
Cumulative foreign currency translation adjustment	9,754	(21,888)
Unrealized gain on pensions and other postretirement plans	595,287	325,921
Cash flow hedges	(1,727)	(738)
Cost of 15,017,167 and 14,687,763 shares of Class B common stock held in treasury	(4,056,993)	(3,920,152)
Total Common Stockholders’ Equity	3,759,302	3,319,239
Noncontrolling Interests	7,091	7,557
Total Equity	3,766,393	3,326,796
Total Liabilities and Equity	6,444,119	5,931,236
Class A Common Stock [Member]
Common Stockholders’ Equity
Common stock	964	964
Accumulated other comprehensive income, net of taxes
Total Equity	964	964
Class B Common Stock [Member]
Common Stockholders’ Equity
Common stock	19,036	19,036
Accumulated other comprehensive income, net of taxes
Total Equity	$ 19,036	$ 19,036