Leases Lessor, Lease Maturity (Details) $ in Millions	Mar. 31, 2019 USD ($)
Lessor, Lease Maturity [Abstract]
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Next Rolling Twelve Months	$ 805
Sales-type and Direct Financing Leases, Lease Receivable, Lease Payments to be Received, Rolling Year Two	693
Sales-type and Direct Financing Leases, Lease Receivable, Lease Payments to be Received, Rolling Year Three	663
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Rolling Year Four	428
Sales-type and Direct Financing Leases, Lease Receivable, Lease Payments to be Received, Rolling Year Five	352
Sales-type and Direct Financing Leases, Lease Receivable, Lease Payments to be Received, after Rolling Year Five	1,430
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received	4,371
Lease Receivable Reconciling Items	471
Sales-type and Direct Financing Leases, Lease Receivable	3,900
Lessor, Operating Lease, Payments to be Received, Next Rolling Twelve Months	183
Lessor, Operating Lease, Payments to be Received, Rolling Year Two	162
Lessor, Operating Lease, Payments to be Received, Rolling Year Three	133
Lessor, Operating Lease, Payments to be Received, Rolling Year Four	105
Lessor, Operating Lease, Payments to be Received, Rolling Year Five	100
Lessor, Operating Lease, Payments to be Received, Thereafter	287
Lessor, Operating Lease, Payments to be Received	$ 970

Lease Receivable Reconciling Items

No definition available.

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- Definition

Lessor, Lease Maturity [Abstract]

+ References

No definition available.

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- Definition

Amount of lease payments to be received by lessor for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919396-209981

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of lease payments to be received by lessor in next rolling twelve months following latest statement of financial position date for operating lease. For interim and annual periods when interim periods are reported on 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 12
-URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919396-209981

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of lease payments to be received by lessor in fifth rolling twelve months following latest statement of financial position date for operating lease. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

+ Details

Name:	us-gaap_LessorOperatingLeasePaymentsToBeReceivedRollingYearFive
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of lease payments to be received by lessor in fourth rolling twelve months following latest statement of financial position date for operating lease. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount of lease payments to be received by lessor in third rolling twelve months following latest statement of financial position date for operating lease. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of lease payments to be received by lessor in second rolling twelve months following latest statement of financial position date for operating lease. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of lease payments to be received by lessor after fifth fiscal year following latest statement of financial position date for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

+ Details

Name:	us-gaap_LessorOperatingLeasePaymentsToBeReceivedThereafter
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases after fifth rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on 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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in fifth rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on 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 rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

+ Details

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Balance Type:	debit
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- Definition

Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in second rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in next rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in fourth rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

+ Details

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