Leases Maturities of Finance Lease Receivables (Details)	Jan. 31, 2020 USD ($)
Leases [Abstract]
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Remainder of Fiscal Year	$ 72,000,000
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Two Years	87,000,000
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Three Years	64,000,000
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Four Years	32,000,000
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Five Years	14,000,000
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Thereafter	5,000,000
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received	274,000,000
Sales-type and Direct Financing Leases, Lease Receivable, Undiscounted Excess Amount	51,000,000
Sales-type and Direct Financing Leases, Lease Receivable	$ 223,000,000

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=77888428&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=77888428&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 latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

+ References

+ Details

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Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in fourth fiscal year following latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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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 the fiscal year following latest fiscal year. Excludes interim and annual period when interim periods are reported on a rolling approach, from latest statement of financial position date.

+ 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=77888428&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 latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

+ 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 latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

+ 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 second fiscal year following latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

+ 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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