This item represents the gain (loss) realized during the period from the sale of investments accounted for under the cost method of accounting and any losses recognized thereon for impairments of other than a temporary nature.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Section S99
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- Definition

The cash inflow associated with the deconsolidation of a previously consolidated subsidiary or sale of an entity that is related to it but not strictly controlled.

+ 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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Subsequent Events - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended	9 Months Ended
	Feb. 14, 2017	Mar. 31, 2017	Sep. 30, 2014
Subsequent Event [Line Items]
Common stock sold			25,000,000
Scenario, Forecast [Member]
Subsequent Event [Line Items]
Cash proceeds sale of common stock		$ 888
Pre-tax gain on sale of common stock		$ 350
Subsequent Event [Member]
Subsequent Event [Line Items]
Common stock sold	23,353,000
Common stock sold per share	$ 38.03