CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
CURRENT ASSETS
Cash and cash equivalents	$ 53,618	$ 141,295
Short-term investments	46,619	33,960
Restricted cash equivalents and short-term investments	21,025	52,693
Accounts receivable, less allowances (2012 - $4,484; 2011 - $5,957)	201,668	149,665
Other accounts receivable, less allowances (2012 - $1,429; 2011 - $1,226)	7,541	7,538
Prepaid expenses	15,818	11,363
Deferred income taxes	36,129	35,481
Prepaid and refundable income taxes	6,317	6,905
Other	9,805	6,186
TOTAL CURRENT ASSETS	398,540	445,086
PROPERTY, PLANT AND EQUIPMENT
Land and structures	242,170	242,120
Revenue equipment	595,542	569,303
Service, office and other equipment	117,285	110,511
Software	99,310	64,229
Leasehold improvements	23,000	21,426
TOTAL PROPERTY, PLANT AND EQUIPMENT, GROSS	1,077,307	1,007,589
Less allowances for depreciation and amortization	614,335	592,171
TOTAL PROPERTY, PLANT AND EQUIPMENT, NET	462,972	415,418
GOODWILL	82,604	3,660
INTANGIBLE ASSETS, net	71,222	2,822
OTHER ASSETS	51,693	49,234
TOTAL ASSETS	1,067,031	916,220
CURRENT LIABILITIES
Bank overdraft and drafts payable	15,327	20,836
Accounts payable	94,561	66,517
Income taxes payable	220	169
Accrued expenses	163,159	151,887
Current portion of long-term debt	46,282	24,262
TOTAL CURRENT LIABILITIES	319,549	263,671
LONG-TERM DEBT, less current portion	133,796	46,750
PENSION AND POSTRETIREMENT LIABILITIES	91,869	106,578
OTHER LIABILITIES	12,630	13,751
DEFERRED INCOME TAXES	46,820	19,855
STOCKHOLDERS' EQUITY
Common stock, $0.01 par value, authorized 70,000,000 shares; issued 2012: 27,262,457 shares; 2011: 27,099,819 shares	273	271
Additional paid-in capital	287,678	286,408
Retained earnings	287,182	295,108
Treasury stock, at cost, 1,677,932 shares	(57,770)	(57,770)
Accumulated other comprehensive loss	(54,996)	(58,402)
TOTAL STOCKHOLDERS' EQUITY	462,367	465,615
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 1,067,031	$ 916,220