Stock-Based Compensation - Nonvested Stock Award Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2016
Number of Shares
Nonvested stock awards at the beginning of the period (in shares)	222,298,000	331,367,000	343,519,000
Granted (in shares)	122,260,000	113,065,000	175,700,000
Vested (in shares)	(121,788,000)	(216,212,000)	(183,045,000)
Forfeited (in shares)	(10,664,000)	(5,922,000)	(4,807,000)
Nonvested stock awards at the end of the period (in shares)	212,106,000	222,298,000	331,367,000
Weighted Average Fair Value
Nonvested stock awards at the beginning of the period (in dollars per share)	$ 66.28	$ 46.09	$ 32.77
Granted (in dollars per share)	101.74	81.77	55.40
Vested (in dollars per share)	60.25	43.62	30.06
Forfeited (in dollars per share)	95.09	59.40	45.06
Nonvested stock awards at the end of the period (in dollars per share)	$ 88.87	$ 66.28	$ 46.09
Aggregate fair value, vested in period	$ 7,338	$ 9,431	$ 5,503
Number of Time-based Shares
Number of Shares
Nonvested stock awards at the beginning of the period (in shares)	196,818,000	331,367,000	343,519,000
Granted (in shares)	94,309,000	86,305,000	175,700,000
Vested (in shares)	(115,943,000)	(214,932,000)	(183,045,000)
Forfeited (in shares)	(6,864,000)	(5,922,000)	(4,807,000)
Nonvested stock awards at the end of the period (in shares)	168,320,000	196,818,000	331,367,000
Number of Performance-based Shares
Number of Shares
Nonvested stock awards at the beginning of the period (in shares)	16,235,000
Granted (in shares)	17,486,000	16,960,000
Vested (in shares)	(5,845,000)	(725,000)
Forfeited (in shares)	(1,800,000)
Nonvested stock awards at the end of the period (in shares)	26,076,000	16,235,000
Number of Market-based Shares
Number of Shares
Nonvested stock awards at the beginning of the period (in shares)	9,245,000
Granted (in shares)	10,465,000	9,800,000
Vested (in shares)	0	(555,000)
Forfeited (in shares)	(2,000,000)
Nonvested stock awards at the end of the period (in shares)	17,710,000	9,245,000

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

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-Publisher FASB
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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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