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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

No definition available.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 210
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-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Number of pending claims pertaining to a loss contingency.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=121557415&loc=d3e14557-108349

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Amount of the accrued liability on an undiscounted basis for malpractice claims (including general and professional liability) at the end of the accounting period.

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Name:	us-gaap_CreditFacilityAxis=us-gaap_LetterOfCreditMember
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Name:	us-gaap_LongtermDebtTypeAxis=dgx_SeniorunsecuredrevolvingcreditfacilityMember
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