Equity Securities, FV-NI, Unrealized Gain (Loss) Restricted

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

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- Definition

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.

+ References

No definition available.

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- Definition

Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117546-209714

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Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Sep. 30, 2018
Derivative [Line Items]
Equity Securities, FV-NI, Unrealized Gain (Loss) Restricted	$ 20	$ 0	$ (1)
Fair value of long term debt	9,600		9,600	$ 9,600
Fair Value, Inputs, Level 1 [Member]
Derivative [Line Items]
Fair value of long term debt	8,600		8,600	8,600
Fair Value, Inputs, Level 2 [Member]
Derivative [Line Items]
Fair value of long term debt	1,000		1,000	$ 1,000
Marketable Securities [Member]
Derivative [Line Items]
Equity Securities, FV-NI, Unrealized Gain (Loss)	21		(1)
Deferred compensation plan assets [Member]
Derivative [Line Items]
Equity Securities, FV-NI, Unrealized Gain (Loss)	$ 7		$ (2)