CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Income Statement [Abstract]
Net revenues	$ 1,906,810	$ 1,903,201	$ 3,843,266	$ 3,724,778
Operating costs and expenses:
Cost of services	1,110,514	1,104,394	2,227,052	2,201,392
Selling, general and administrative	440,788	462,789	941,429	910,647
Amortization of intangible assets	20,169	18,592	40,400	28,441
Other operating expense, net	591	572	52	236,484
Total operating costs and expenses	1,572,062	1,586,347	3,208,933	3,376,964
Operating income	334,748	316,854	634,333	347,814
Other income (expense):
Interest expense, net	(41,942)	(46,581)	(84,275)	(84,510)
Equity earnings in unconsolidated joint ventures	7,372	7,869	14,981	15,568
Other (expense) income, net	(1,256)	(346)	3,501	1,862
Total non-operating expenses, net	(35,826)	(39,058)	(65,793)	(67,080)
Income from continuing operations before taxes	298,922	277,796	568,540	280,734
Income tax expense	112,394	105,762	213,771	154,988
Income from continuing operations	186,528	172,034	354,769	125,746
Income (loss) from discontinued operations, net of taxes	(55)	(507)	219	(881)
Net income	186,473	171,527	354,988	124,865
Less: Net income attributable to noncontrolling interests	8,768	8,384	18,165	15,583
Net income attributable to Quest Diagnostics	177,705	163,143	336,823	109,282
Amounts attributable to Quest Diagnostics' stockholders:
Income from continuing operations	177,760	163,650	336,604	110,163
Income (loss) from discontinued operations, net of taxes	(55)	(507)	219	(881)
Net income attributable to Quest Diagnostics	$ 177,705	$ 163,143	$ 336,823	$ 109,282
Earnings per share attributable to Quest Diagnostics' common stockholders - basic:
Income from continuing operations	$ 1.12	$ 1.03	$ 2.12	$ 0.68
Income (loss) from discontinued operations, per basic share	$ 0.00	$ 0.00	$ 0.00	$ 0.00
Net income	$ 1.12	$ 1.03	$ 2.12	$ 0.68
Earnings per share attributable to Quest Diagnostics' common stockholders - diluted:
Income from continuing operations	$ 1.11	$ 1.02	$ 2.10	$ 0.68
Income (loss) from discontinued operations, per diluted share	$ 0.00	$ 0.00	$ 0.00	$ (0.01)
Net income	$ 1.11	$ 1.02	$ 2.10	$ 0.67
Weighted average common shares outstanding:
Basic	158,477	157,607	158,385	159,548
Diluted	159,784	159,352	159,745	161,278
Dividends per common share	$ 0.17	$ 0.10	$ 0.34	$ 0.20