CONDENSED CONSOLIDATED STATEMENTS OF FINANCIAL POSITION (Unaudited) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
ASSETS
Cash and cash equivalents	$ 116,734	$ 65,082
Trade receivables, short-term, net of allowance for doubtful accounts of $8,137 and $8,211, respectively	80,902	68,920
Financed receivables, short-term, net of allowance for doubtful accounts of $1,741 and $1,842, respectively	12,740	11,823
Materials and supplies	11,836	11,847
Deferred income taxes, net	34,665	33,338
Other current assets	19,804	14,982
Total Current Assets	276,681	205,992
Equipment and property, net	85,348	82,263
Goodwill	212,201	212,477
Customer contracts and other intangible assets, net	134,763	141,789
Deferred income taxes, net	25,903	26,841
Financed receivables, long-term, net of allowance for doubtful accounts of $1,459 and $1,309, respectively	12,722	11,681
Other assets	13,246	11,463
Total Assets	760,864	692,506
LIABILITIES
Accounts payable	26,106	24,854
Accrued insurance	26,551	24,164
Accrued compensation and related liabilities	63,695	60,042
Unearned revenues	100,114	87,753
Other current liabilities	32,093	31,603
Total current liabilities	248,559	228,416
Accrued insurance, less current portion	28,094	31,283
Accrued pension	41,509	43,271
Long-term accrued liabilities	35,410	34,580
Total Liabilities	353,572	337,550
STOCKHOLDERS' EQUITY
Preferred stock, without par value; 500,000 shares authorized, zero shares issued
Common stock, par value $1 per share; 250,000,000 shares authorized, 145,878,996 and 146,015,082 shares issued and outstanding, respectively	145,879	146,015
Paid in capital	50,964	45,156
Accumulated other comprehensive loss	(58,218)	(56,967)
Retained earnings	268,667	220,752
Total Stockholders Equity	407,292	354,956
Total Liabilities and Stockholders Equity	$ 760,864	$ 692,506