CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Statement of Other Comprehensive Income [Abstract]
Net income	$ 186,473	$ 171,527	$ 354,988	$ 124,865
Other comprehensive income (loss):
Currency translation	(19,183)	1,970	(967)	26,474
Market valuation, net of tax	44	(346)	245	(1,596)
Net deferred loss on cash flow hedges, net of tax	210	210	420	(1,461)
Other comprehensive (loss) income	(18,929)	1,834	(302)	23,417
Comprehensive income	167,544	173,361	354,686	148,282
Less: Comprehensive income attributable to noncontrolling interests	8,768	8,384	18,165	15,583
Comprehensive income attributable to Quest Diagnostics	$ 158,776	$ 164,977	$ 336,521	$ 132,699

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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