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Return of reserve capital to purchase minority ownership interests.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Carrying amount of the equity interests owned by noncontrolling shareholders, partners, or other equity holders in joint ventures included in the entity's consolidated financial statements.

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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.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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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	Sep. 30, 2016 USD ($)
Noncontrolling Interest [Line Items]
Non-controlling interest balances			$ 68
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%