Leases Maturities of Finance Lease Receivables (Details)	Jul. 31, 2020 USD ($)
Leases [Abstract]
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Remainder of Fiscal Year	$ 72,000,000
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Two	70,000,000
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Three	49,000,000
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Four	28,000,000
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Five	13,000,000
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, after Year Five	3,000,000
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received	235,000,000
Sales-type and Direct Financing Leases, Lease Receivable, Undiscounted Excess Amount	50,000,000
Sales-type and Direct Financing Leases, Lease Receivable	$ 185,000,000

No definition available.

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- Definition

Present value of lease payments not yet received by lessor and amount expected to be derived from underlying asset, following end of lease term guaranteed by lessee or other third party unrelated to lessor, from sales-type and direct financing leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919391-209981

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919379-209981

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- Definition

Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases.

+ References

+ Details

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- Definition

Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in remainder of current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919391-209981

+ Details

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- Definition

Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of undiscounted lease receivable in excess of discounted receivable for sales-type and direct financing leases.

+ References

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