BUSINESS ACQUISITIONS (Pro Forma) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Business Combinations [Abstract]
Pro forma net revenues	$ 7,520	$ 7,622
Pro forma income from continuing operations	$ 585	$ 855
Earnings per share attributable to Quest Diagnostics’ common stockholders - basic:
Pro forma income from continuing operations	$ 3.79	$ 5.40
Earnings per share attributable to Quest Diagnostics’ common stockholders - diluted:
Pro forma income from continuing operations	$ 3.77	$ 5.36

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- Definition

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

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

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

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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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