Fair Value of Financial Investments (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Fair value of financial investments and liabilities
Total financial investments	$ 50	$ 50
Cost basis available-for-sale securities	19	19
Pre-tax unrealized gains, available-for-sale securities	3	3
Recorded basis, available for sale securities	22	22
Recurring \| Level 3
Fair value of financial investments and liabilities
Recurring investments, Available-for-sale securities	22	22
Recurring \| Auction rate securities \| Level 3
Fair value of financial investments and liabilities
Recurring investments, Available-for-sale securities	22	22
Non-recurring investments \| Equity method investments
Fair value of financial investments and liabilities
Equity method investments	13	11
Non-recurring investments \| Private equity funds
Fair value of financial investments and liabilities
Non-recurring investments	12	14
Non-recurring investments \| Other investments
Fair value of financial investments and liabilities
Non-recurring investments	$ 3	$ 3

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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- Definition

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (aa)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.2)

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- Definition

Amount of debt securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

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-Name Accounting Standards Codification

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-SubTopic 320

-Section 50

-Paragraph 2

-Subparagraph (b)-(g)

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- Definition

Total of debt securities categorized neither as held-to-maturity nor trading which are intended be sold or mature more than one year from the balance sheet date or operating cycle, if longer.

+ References

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- Definition

Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Topic 210

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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

The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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