BUSINESS ACQUISITIONS (Pro Forma) (Details) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2014 USD ($) $ / shares
Business Combinations [Abstract]
Pro forma net revenues \| $	$ 7,520
Pro forma income from continuing operations \| $	$ 585
Earnings per share attributable to Quest Diagnostics’ common stockholders - basic:
Pro forma income from continuing operations \| $ / shares	$ 3.79
Earnings per share attributable to Quest Diagnostics’ common stockholders - diluted:
Pro forma income from continuing operations \| $ / shares	$ 3.77

Business Acquisition Pro Forma Common Shares, Basic [Abstract]

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Business Acquisition Pro Forma Common Shares, Diluted [Abstract]

+ References

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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
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

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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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