Fair Value Measurements - Additional Information (Details) - USD ($) |
3 Months Ended | 9 Months Ended | 12 Months Ended | |||
|---|---|---|---|---|---|---|
Jun. 30, 2018 |
Jun. 30, 2017 |
Jun. 30, 2018 |
Jun. 30, 2017 |
Sep. 30, 2015 |
Sep. 30, 2017 |
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| Fair Value Disclosures [Abstract] | ||||||
| Litigation Settlement, Amount | $ 398,000,000 | |||||
| Increase (Decrease) in Restricted Cash | $ 335,000,000 | |||||
| Restricted Investments, Current | $ 30,000,000 | $ 30,000,000 | $ 30,000,000 | |||
| Other than Temporary Impairment Losses, Investments, Available-for-sale Securities | 0 | $ 0 | 0 | $ 0 | ||
| Other financial instruments [Abstract] | ||||||
| Long-term Debt, Carrying Value | 2,483,000,000 | 2,483,000,000 | 2,615,000,000 | |||
| Long-term Debt, Fair Value | $ 2,541,000,000 | $ 2,541,000,000 | $ 2,768,000,000 | |||
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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- References No definition available.
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- Definition The net cash inflow or outflow for the increase (decrease) associated with funds that are not available for withdrawal or use (such as funds held in escrow) and are associated with underlying transactions that are classified as investing activities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount awarded from other party in judgment or settlement of litigation. No definition available.
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- Definition The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. No definition available.
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- Definition The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income. No definition available.
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- Definition The current cash, cash equivalents and investments that are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. Includes current cash equivalents and investments that are similarly restricted as to withdrawal, usage or disposal. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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