Allowance for Credit Losses - Allowance for Credit Losses on Finance Receivables and Investments in Operating Leases (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Allowance for Credit Losses on Finance Receivables and Investments in Operating Leases
Allowance for credit losses at beginning of period	$ 600	$ 611	$ 597	$ 622
Charge-offs	(105)	(124)	(218)	(243)
Recoveries	23	22	50	45
Provision for credit losses	67	127	156	212
Allowance for credit losses at end of period	$ 585	$ 636	$ 585	$ 636

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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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.

+ References

No definition available.

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

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