Consolidated Statement Of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Continuing Operations
Service revenues and sales	$ 354,353	$ 341,439	$ 1,061,466	$ 1,005,717
Cost of services provided and goods sold (excluding depreciation)	256,610	245,063	771,423	722,118
Selling, general and administrative expenses	52,955	47,618	155,892	153,696
Depreciation	6,557	6,313	19,178	18,959
Amortization	1,135	1,134	3,375	3,243
Other operating expenses	1,126		1,126
Total costs and expenses	318,383	300,128	950,994	898,016
Income from operations	35,970	41,311	110,472	107,701
Interest expense	(3,743)	(3,555)	(11,032)	(10,260)
Other income/(expense)- net	1,840	(1,935)	2,965	881
Income before income taxes	34,067	35,821	102,405	98,322
Income taxes	(13,222)	(13,934)	(39,841)	(38,048)
Net income	$ 20,845	$ 21,887	$ 62,564	$ 60,274
Earnings Per Share
Net income	$ 1.10	$ 1.06	$ 3.30	$ 2.88
Average number of shares outstanding	18,960	20,674	18,977	20,934
Diluted Earnings Per Share
Net income	$ 1.07	$ 1.04	$ 3.23	$ 2.82
Average number of shares outstanding	19,404	21,055	19,382	21,400
Cash Dividends Per Share	$ 0.18	$ 0.16	$ 0.50	$ 0.44