Acquisitions and Dispositions - Additional Information (Detail) $ in Millions	9 Months Ended
Sep. 30, 2016 USD ($) Hospital	Sep. 30, 2015 USD ($) Hospital
Business Acquisition [Line Items]
Number of hospitals acquired \| Hospital	3	1
Proceeds from sale of business	$ 23	$ 27
Hospitals [Member]
Business Acquisition [Line Items]
Cash paid for acquisition	343	15
Nonhospital Health Care [Member]
Business Acquisition [Line Items]
Cash paid for acquisition	125	169
Real Estate and Other Investments [Member]
Business Acquisition [Line Items]
Pretax gain (loss) on sales of business	8	2
Proceeds from sale of business	$ 23	$ 27

Number of hospitals acquired.

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+ References

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Amount before tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

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