Financial Instruments (Contractual Maturity Date of Marketable Debt Securities) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014
Fair Value Disclosures [Abstract]
Due in 1 year	$ 8,854
Due in 1 year through 5 years	22,010
Due in 5 years through 10 years	6,790
Due after 10 years	8,192
Total	$ 45,846

Fair value of available-for-sale debt securities maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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-Name Accounting Standards Codification

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Fair value of available-for-sale debt securities maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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Fair value of available-for-sale debt securities maturing after the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Fair value of available-for-sale debt securities maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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

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