Other Noncurrent Liabilities and Redeemable/Noncontrolling Interests - Additional Information (Detail) $ in Millions	1 Months Ended	3 Months Ended
May 31, 2016 USD ($) Hospital	Jun. 30, 2016 USD ($) Hospital
Noncontrolling Interest [Line Items]
Non-controlling interest balances		$ 65
Redeemable non-controlling interest balances		$ 9
Minimum
Noncontrolling Interest [Line Items]
Ownership interests purchased		26.10%
Maximum
Noncontrolling Interest [Line Items]
Ownership interests purchased		27.50%
Acute Care Hospital Services \| Las Vegas, Nevada
Noncontrolling Interest [Line Items]
Number of hospital facilities \| Hospital	6	6
Payments to purchase minority ownership interests	$ 445	$ 445
Purchase price of minority ownership interests	418	418
Return of reserve capital to purchase of minority ownership interests	$ 27	$ 27
Percentage of noncontrolling, minority ownership interests held by outside owners		5.00%
Acute Care Hospital Services \| Las Vegas, Nevada \| Minimum
Noncontrolling Interest [Line Items]
Ownership interests purchased		26.10%
Acute Care Hospital Services \| Las Vegas, Nevada \| Maximum
Noncontrolling Interest [Line Items]
Ownership interests purchased		27.50%
Acute Care Hospital Services \| Washington, District of Columbia
Noncontrolling Interest [Line Items]
Percentage of noncontrolling, minority ownership interests held by outside owners		20.00%
Acute Care Hospital Services \| Laredo, Texas
Noncontrolling Interest [Line Items]
Percentage of noncontrolling, minority ownership interests held by outside owners		11.00%
Behavioral Health Services \| Philadelphia, Pennsylvania
Noncontrolling Interest [Line Items]
Percentage of noncontrolling, minority ownership interests held by outside owners		20.00%

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