Lessee, Operating Lease, Lease Not yet Commenced, Amount

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

Term of lessee's operating lease not yet commenced, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount of loss from impairment of right-of-use asset from operating lease.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

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- Definition

The total amount of sublease rental income recognized during the period that reduces the entity's rent expense incurred under operating leases.

+ References

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Leases (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Leases (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Apr. 01, 2019	Mar. 31, 2019
Concentration Risk [Line Items]
ROU assets	$ 1,921				$ 1,700
Lease liabilities	2,268
Operating lease, impairment loss	9
Lessee, operating lease, lease not yet commenced, amount	$ 45
Lessee, operating lease, lease not yet commenced, term	12 months
Net rental costs		$ 383	$ 354
Rentals from subleases		$ 8	$ 8
Minimum
Concentration Risk [Line Items]
Non-cancelable operating leases, term	10 years
Maximum
Concentration Risk [Line Items]
Non-cancelable operating leases, term	25 years
Office Space \| Lease Concentration Risk \| Lease Obligations
Concentration Risk [Line Items]
Lease obligations for the use of office space (as a percent)	99.00%
JLT Transaction
Concentration Risk [Line Items]
ROU assets				$ 400
Lease liabilities				$ 400