SUMMARIZED FINANCIAL INFORMATION (Condensed Consolidating Balance Sheet) (Details) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2010	Dec. 31, 2009
Cash and cash equivalents	$ 110,825	$ 449,301	$ 369,261	$ 534,256
Accounts receivable, net	936,259	845,299
Other current assets	349,193	310,817
Total current assets	1,396,277	1,605,417
Property, plant and equipment, net	806,043	834,376
Goodwill and intangible assets, net	6,850,799	5,898,343
Intercompany receivable (payable)
Investment in subsidiaries
Other assets	273,352	189,494
Total assets	9,326,471	8,527,630
Accounts payable and accrued expenses	928,162	865,272
Short-term borrowings and current portion of long-term debt	835,910	348,996
Total current liabilities	1,764,072	1,214,268
Long-term debt	3,367,847	2,641,160
Other liabilities	649,588	618,077
Quest Diagnostics stockholders' equity	3,522,386	4,033,480
Noncontrolling interests	22,578	20,645
Total stockholders' equity	3,544,964	4,054,125	3,880,705	4,011,464
Total liabilities and stockholders' equity	9,326,471	8,527,630
Parent [Member]
Cash and cash equivalents	53,183	392,525	321,426	464,958
Accounts receivable, net	19,090	15,913
Other current assets	62,436	55,723
Total current assets	134,709	464,161
Property, plant and equipment, net	164,278	179,624
Goodwill and intangible assets, net	155,138	155,596
Intercompany receivable (payable)	(394,806)	84,107
Investment in subsidiaries	7,854,227	6,195,557
Other assets	310,661	227,822
Total assets	8,224,207	7,306,867
Accounts payable and accrued expenses	740,094	623,610
Short-term borrowings and current portion of long-term debt	743,346	203,659
Total current liabilities	1,483,440	827,269
Long-term debt	3,024,344	2,295,709
Other liabilities	194,037	150,409
Quest Diagnostics stockholders' equity	3,522,386	4,033,480
Noncontrolling interests
Total stockholders' equity	3,522,386	4,033,480
Total liabilities and stockholders' equity	8,224,207	7,306,867
Subsidiary Guarantors [Member]
Cash and cash equivalents	10,914	928	191	17,457
Accounts receivable, net	172,687	135,417
Other current assets	190,949	165,099
Total current assets	374,550	301,444
Property, plant and equipment, net	601,139	616,114
Goodwill and intangible assets, net	6,246,343	5,279,371
Intercompany receivable (payable)	680,511	231,268
Investment in subsidiaries
Other assets	43,311	10,090
Total assets	7,945,854	6,438,287
Accounts payable and accrued expenses	140,012	190,334
Short-term borrowings and current portion of long-term debt	6,944	144,004
Total current liabilities	146,956	334,338
Long-term debt	18,499	19,342
Other liabilities	537,677	512,681
Quest Diagnostics stockholders' equity	7,242,722	5,571,926
Noncontrolling interests
Total stockholders' equity	7,242,722	5,571,926
Total liabilities and stockholders' equity	7,945,854	6,438,287
Non-Guarantor Subsidiaries [Member]
Cash and cash equivalents	46,728	55,848	47,644	51,841
Accounts receivable, net	744,482	693,969
Other current assets	96,169	96,183
Total current assets	887,379	846,000
Property, plant and equipment, net	40,626	38,638
Goodwill and intangible assets, net	449,318	463,376
Intercompany receivable (payable)	(285,705)	(315,375)
Investment in subsidiaries
Other assets	50,011	48,319
Total assets	1,141,629	1,080,958
Accounts payable and accrued expenses	48,417	57,516
Short-term borrowings and current portion of long-term debt	85,620	1,333
Total current liabilities	134,037	58,849
Long-term debt	325,004	326,109
Other liabilities	48,505	51,724
Quest Diagnostics stockholders' equity	611,505	623,631
Noncontrolling interests	22,578	20,645
Total stockholders' equity	634,083	644,276
Total liabilities and stockholders' equity	1,141,629	1,080,958
Eliminations [Member]
Cash and cash equivalents
Accounts receivable, net
Other current assets	(361)	(6,188)
Total current assets	(361)	(6,188)
Property, plant and equipment, net
Goodwill and intangible assets, net
Intercompany receivable (payable)
Investment in subsidiaries	(7,854,227)	(6,195,557)
Other assets	(130,631)	(96,737)
Total assets	(7,985,219)	(6,298,482)
Accounts payable and accrued expenses	(361)	(6,188)
Short-term borrowings and current portion of long-term debt
Total current liabilities	(361)	(6,188)
Long-term debt
Other liabilities	(130,631)	(96,737)
Quest Diagnostics stockholders' equity	(7,854,227)	(6,195,557)
Noncontrolling interests
Total stockholders' equity	(7,854,227)	(6,195,557)
Total liabilities and stockholders' equity	$ (7,985,219)	$ (6,298,482)