CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Income Statement [Abstract]
Net revenues	$ 1,906,405	$ 1,864,655	$ 5,631,183	$ 5,544,885
Operating costs and expenses:
Cost of services	1,116,574	1,091,465	3,317,966	3,236,809
Selling, general and administrative	446,595	426,562	1,357,242	1,276,707
Amortization of intangible assets	19,402	9,915	47,843	28,544
Other operating (income) expense, net	1,781	(154)	238,265	1,502
Total operating costs and expenses	1,584,352	1,527,788	4,961,316	4,543,562
Operating income	322,053	336,867	669,867	1,001,323
Other income (expense):
Interest expense, net	(43,408)	(36,200)	(127,918)	(108,522)
Equity earnings in unconsolidated joint ventures	7,301	7,201	22,869	22,550
Other (expense) income, net	(2,677)	3,150	(815)	2,043
Total non-operating expenses, net	(38,784)	(25,849)	(105,864)	(83,929)
Income from continuing operations before taxes	283,269	311,018	564,003	917,394
Income tax expense	101,126	102,902	256,114	333,931
Income from continuing operations	182,143	208,116	307,889	583,463
Loss from discontinued operations, net of taxes	(250)	(360)	(1,131)	(678)
Net income	181,893	207,756	306,758	582,785
Less: Net income attributable to noncontrolling interests	10,045	9,681	25,628	27,647
Net income attributable to Quest Diagnostics	171,848	198,075	281,130	555,138
Amounts attributable to Quest Diagnostics' stockholders:
Income from continuing operations	172,098	198,435	282,261	555,816
Loss from discontinued operations, net of taxes	(250)	(360)	(1,131)	(678)
Net income attributable to Quest Diagnostics	$ 171,848	$ 198,075	$ 281,130	$ 555,138
Earnings per share attributable to Quest Diagnostics' common stockholders - basic:
Income from continuing operations	$ 1.08	$ 1.14	$ 1.76	$ 3.12
Loss from discontinued operations, per basic share			$ (0.01)
Net income	$ 1.08	$ 1.14	$ 1.75	$ 3.12
Earnings per share attributable to Quest Diagnostics' common stockholders - diluted:
Income from continuing operations	$ 1.08	$ 1.13	$ 1.75	$ 3.09
Loss from discontinued operations, per diluted share	$ (0.01)		$ (0.01)
Net income	$ 1.07	$ 1.13	$ 1.74	$ 3.09
Weighted average common shares outstanding:
Basic	157,816	173,229	158,971	177,456
Diluted	159,002	174,315	160,519	179,153
Dividends per common share	$ 0.1	$ 0.1	$ 0.3	$ 0.3