SUMMARIZED FINANCIAL INFORMATION (Condensed Consolidating Statement of Operations) (Details) (USD $) In Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Net revenues	$ 1,903,201	$ 1,874,727	$ 3,724,778	$ 3,680,230
Cost of services	1,104,394	1,078,971	2,201,392	2,145,344
Selling, general and administrative	462,789	419,412	910,647	850,145
Amortization of intangible assets	18,592	9,270	28,441	18,629
Royalty (income) expense
Other operating expense, net	572	1,180	236,484	1,656
Total operating costs and expenses	1,586,347	1,508,833	3,376,964	3,015,774
Operating income (loss)	316,854	365,894	347,814	664,456
Non-operating expenses, net	(39,058)	(36,101)	(67,080)	(58,080)
Income (loss) from continuing operations before taxes	277,796	329,793	280,734	606,376
Income tax expense	105,762	125,651	154,988	231,029
Income from continuing operations	172,034	204,142	125,746	375,347
Loss from discontinued operations, net of taxes	(507)	(266)	(881)	(318)
Equity earnings from subsidiaries
Net income	171,527	203,876	124,865	375,029
Less: Net income attributable to noncontrolling interests	8,384	9,261	15,583	17,966
Net income attributable to Quest Diagnostics	163,143	194,615	109,282	357,063
Parent [Member]
Net revenues	203,321	218,419	401,810	429,640
Cost of services	121,342	129,236	244,933	251,823
Selling, general and administrative	35,526	21,273	73,962	44,351
Amortization of intangible assets	543	18	706	35
Royalty (income) expense	(104,418)	(105,316)	(206,774)	(206,808)
Other operating expense, net	28	(1,346)	236,306	(321)
Total operating costs and expenses	53,021	43,865	349,133	89,080
Operating income (loss)	150,300	174,554	52,677	340,560
Non-operating expenses, net	(45,706)	(39,974)	(84,126)	(70,533)
Income (loss) from continuing operations before taxes	104,594	134,580	(31,449)	270,027
Income tax expense	40,382	52,577	36,768	104,062
Income from continuing operations	64,212	82,003	(68,217)	165,965
Loss from discontinued operations, net of taxes
Equity earnings from subsidiaries	98,931	112,612	177,499	191,098
Net income	163,143	194,615	109,282	357,063
Less: Net income attributable to noncontrolling interests
Net income attributable to Quest Diagnostics	163,143	194,615	109,282	357,063
Subsidiary Guarantors [Member]
Net revenues	1,577,305	1,540,722	3,080,649	3,023,312
Cost of services	909,681	886,783	1,817,071	1,766,570
Selling, general and administrative	342,577	312,465	654,306	626,583
Amortization of intangible assets	16,048	7,601	24,197	15,232
Royalty (income) expense	104,418	105,316	206,774	206,808
Other operating expense, net	585	233	371	466
Total operating costs and expenses	1,373,309	1,312,398	2,702,719	2,615,659
Operating income (loss)	203,996	228,324	377,930	407,653
Non-operating expenses, net	(53,301)	(54,940)	(110,455)	(121,385)
Income (loss) from continuing operations before taxes	150,695	173,384	267,475	286,268
Income tax expense	59,578	67,331	105,743	113,078
Income from continuing operations	91,117	106,053	161,732	173,190
Loss from discontinued operations, net of taxes	(507)	(266)	(881)	(318)
Equity earnings from subsidiaries
Net income	90,610	105,787	160,851	172,872
Less: Net income attributable to noncontrolling interests
Net income attributable to Quest Diagnostics	90,610	105,787	160,851	172,872
Non-Guarantor Subsidiaries [Member]
Net revenues	189,592	181,373	380,879	373,709
Cost of services	73,371	62,952	139,388	126,951
Selling, general and administrative	92,150	93,236	197,203	194,104
Amortization of intangible assets	2,001	1,651	3,538	3,362
Royalty (income) expense
Other operating expense, net	(41)	2,293	(193)	1,511
Total operating costs and expenses	167,481	160,132	339,936	325,928
Operating income (loss)	22,111	21,241	40,943	47,781
Non-operating expenses, net	396	588	3,765	2,300
Income (loss) from continuing operations before taxes	22,507	21,829	44,708	50,081
Income tax expense	5,802	5,743	12,477	13,889
Income from continuing operations	16,705	16,086	32,231	36,192
Loss from discontinued operations, net of taxes
Equity earnings from subsidiaries
Net income	16,705	16,086	32,231	36,192
Less: Net income attributable to noncontrolling interests	8,384	9,261	15,583	17,966
Net income attributable to Quest Diagnostics	8,321	6,825	16,648	18,226
Eliminations [Member]
Net revenues	(67,017)	(65,787)	(138,560)	(146,431)
Cost of services
Selling, general and administrative	(7,464)	(7,562)	(14,824)	(14,893)
Amortization of intangible assets
Royalty (income) expense
Other operating expense, net
Total operating costs and expenses	(7,464)	(7,562)	(14,824)	(14,893)
Operating income (loss)	(59,553)	(58,225)	(123,736)	(131,538)
Non-operating expenses, net	59,553	58,225	123,736	131,538
Income (loss) from continuing operations before taxes
Income tax expense
Income from continuing operations
Loss from discontinued operations, net of taxes
Equity earnings from subsidiaries	(98,931)	(112,612)	(177,499)	(191,098)
Net income	(98,931)	(112,612)	(177,499)	(191,098)
Less: Net income attributable to noncontrolling interests
Net income attributable to Quest Diagnostics	$ (98,931)	$ (112,612)	$ (177,499)	$ (191,098)