Leases - Future minimum lease payments under capital leases (Detail) ¥ in Millions	Sep. 30, 2018 JPY (¥)
Leases [Abstract]
Total minimum lease payments	¥ 44,409
Less: Amount representing interest	(26,798)
Present value of net minimum lease payments	¥ 17,611

Amount necessary to reduce net minimum lease payments to present value for capital leases.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84164817&loc=d3e45280-112737

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- Definition

Amount of minimum lease payments for capital leases net of executory costs, which include amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

+ References

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- Definition

Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

+ References

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- References

No definition available.

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