Fair Value Measurements (Tables)

3 Months Ended

Apr. 30, 2017

Fair Value Disclosures [Abstract]

Notional amounts and fair values of derivatives

As of April 30, 2017 and January 31, 2017, the notional amounts and fair values of these derivatives were as follows:

	April 30, 2017					January 31, 2017
(Amounts in millions)	Notional Amount		Fair Value			Notional Amount		Fair Value
Receive fixed-rate, pay variable-rate interest rate swaps designated as fair value hedges	$	5,000	$	16		$	5,000	$	(4	)
Receive fixed-rate, pay fixed-rate cross-currency swaps designated as net investment hedges	2,250		395			2,250		471
Receive fixed-rate, pay fixed-rate cross-currency swaps designated as cash flow hedges	4,019		(524		)	3,957		(618		)
Total	$	11,269	$	(113	)	$	11,207	$	(151	)

Available-for-sale securities

The cost basis and fair value of the Company's available-for-sale securities as of April 30, 2017 and January 31, 2017, are as follows: 

	April 30, 2017				January 31, 2017
(Amounts in millions)	Cost Basis		Fair Value		Cost Basis		Fair Value
Available-for-sale securities	$	1,901	$	2,527	$	1,901	$	2,046

Carrying value and fair value of long-term debt

The carrying value and fair value of the Company's long-term debt as of April 30, 2017 and January 31, 2017, are as follows: 

	April 30, 2017				January 31, 2017
(Amounts in millions)	Carrying Value		Fair Value		Carrying Value		Fair Value
Long-term debt, including amounts due within one year	$	37,030	$	44,058	$	38,271	$	44,602