CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Income Statement [Abstract]
Net revenues	$ 1,936,456	$ 1,821,577
Operating costs and expenses:
Cost of services	1,116,538	1,096,998
Selling, general and administrative	500,641	447,858
Amortization of intangible assets	20,231	9,849
Other operating (income) expense, net	(539)	235,912
Total operating costs and expenses	1,636,871	1,790,617
Operating income	299,585	30,960
Other income (expense):
Interest expense, net	(42,333)	(37,929)
Equity earnings in unconsolidated joint ventures	7,609	7,699
Other income, net	4,757	2,208
Total non-operating expenses, net	(29,967)	(28,022)
Income from continuing operations before taxes	269,618	2,938
Income tax expense	101,377	49,226
Income (loss) from continuing operations	168,241	(46,288)
Income (loss) from discontinued operations, net of taxes	274	(374)
Net income (loss)	168,515	(46,662)
Less: Net income attributable to noncontrolling interests	9,397	7,199
Net income (loss) attributable to Quest Diagnostics	159,118	(53,861)
Amounts attributable to Quest Diagnostics' stockholders:
Income (loss) from continuing operations	158,844	(53,487)
Income (loss) from discontinued operations, net of taxes	274	(374)
Net income (loss) attributable to Quest Diagnostics	$ 159,118	$ (53,861)
Earnings (loss) per share attributable to Quest Diagnostics' common stockholders - basic:
Income (loss) from continuing operations	$ 1.00	$ (0.33)
Income (loss) from discontinued operations, per basic share	$ 0.00	$ 0.00
Net income (loss)	$ 1.00	$ (0.33)
Earnings (loss) per share attributable to Quest Diagnostics' common stockholders - diluted:
Income (loss) from continuing operations	$ 0.99	$ (0.33)
Income (loss) from discontinued operations, per diluted share	$ 0.00	$ 0.00
Net income (loss)	$ 0.99	$ (0.33)
Weighted average common shares outstanding:
Basic	158,293	161,489
Diluted	159,706	161,489
Dividends per common share	$ 0.17	$ 0.10