BUSINESS ACQUISITION (Pro Forma) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Business Acquisition [Line Items]
Pro forma net revenues	$ 1,906	$ 1,929	$ 3,733	$ 3,829
Pro forma income from continuing operations	$ 143	$ 163	$ 252	$ 286
Earnings per share attributable to Quest Diagnostics’ common stockholders - basic:
Pro forma income from continuing operations	$ 0.92	$ 0.99	$ 1.63	$ 1.72
Earnings per share attributable to Quest Diagnostics’ common stockholders - diluted:
Pro forma income from continuing operations	$ 0.92	$ 1.00	$ 1.62	$ 1.71

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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