The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 45
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the 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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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third 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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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second 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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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Goodwill and Intangible Assets, Net - Narrative - Intangible Assets (Details) - USD ($)	3 Months Ended		6 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Mar. 31, 2017
Goodwill [Line Items]
Amortization expense of intangible assets	$ 126,000,000	$ 115,000,000	$ 247,000,000	$ 230,000,000
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]
Estimated annual amortization expense, remainder of 2018	224,000,000		224,000,000
Estimated annual amortization expense, 2019	434,000,000		434,000,000
Estimated annual amortization expense, 2020	418,000,000		418,000,000
Estimated annual amortization expense, 2021	400,000,000		400,000,000
Estimated annual amortization expense, 2022	369,000,000		369,000,000
Estimated annual amortization expense, thereafter	2,361,000,000		2,361,000,000
Distribution Solutions
Goodwill [Line Items]
Accumulated goodwill impairment losses	350,000,000		350,000,000		$ 0
Technology Solutions
Goodwill [Line Items]
Accumulated goodwill impairment losses	$ 290,000,000		$ 290,000,000		$ 0