CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Consolidated Statements of Comprehensive Income [Abstract]
Net income (loss)	$ 168,515	$ (46,662)
Other comprehensive income (loss):
Currency translation	18,216	24,504
Market valuation, net of tax	201	(1,250)
Net deferred loss on cash flow hedges	210	(1,671)
Other comprehensive income	18,627	21,583
Comprehensive income (loss)	187,142	(25,079)
Less: Comprehensive income attributable to noncontrolling interests	9,397	7,199
Comprehensive income (loss) attributable to Quest Diagnostics	$ 177,745	$ (32,278)

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