Leases (Supplemental Lease Information) (Details) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($)
Leases [Abstract]
Operating cash flows from operating leases	$ 18
Operating leases	$ 7
Operating leases	6 years
Operating leases	2.79%

No definition available.

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- Definition

Discount rate used by lessee to determine present value of operating lease payments.

+ References

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-Publisher FASB
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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

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-Publisher FASB
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- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
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- Definition

Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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