SUPPLEMENTAL CASH FLOW & OTHER DATA (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Supplemental Cash Flow Elements [Abstract]
Depreciation expense	$ 51,686	$ 54,127	$ 103,629	$ 107,643
Interest expense	(42,639)	(47,231)	(85,626)	(85,510)
Interest income	697	650	1,351	1,000
Interest expense, net	(41,942)	(46,581)	(84,275)	(84,510)
Interest paid	32,208	17,539	81,990	72,583
Income taxes paid	192,556	97,119	202,809	107,721
Assets acquired under capital leases	1,763	1,876	2,955	2,697
Fair value of assets acquired	0	1,555,444	50,800	1,555,444
Fair value of liabilities assumed	0	148,192	269	148,192
Fair value of net assets acquired	0	1,407,252	50,531	1,407,252
Merger consideration paid (payable)	12	(158,560)	37	(158,560)
Cash paid for business acquisitions	12	1,248,692	50,568	1,248,692
Less: Cash acquired	0	112,312	0	112,312
Business acquisitions, net of cash acquired	$ 12	$ 1,136,380	$ 50,568	$ 1,136,380