Leases Lease Cost and Supplemental Information (Details) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($) Rate
Leases [Abstract]
Operating Lease, Cost	$ 9
Short-term Lease, Cost	3
Finance Lease, Right-of-Use Asset, Amortization	1
Finance Lease, Interest Expense	1
Variable Lease, Cost	1
Finance Lease, Principal Payments	1
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	$ 1
Operating Lease, Weighted Average Remaining Lease Term	8 years 9 months 29 days
Finance Lease, Weighted Average Remaining Lease Term	2 years 6 months 3 days
Lessee, Operating Lease, Discount Rate \| Rate	12.19%
Lessee, Finance Lease, Discount Rate \| Rate	9.00%

Amount of interest expense on finance lease liability.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
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-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Balance Type:	debit
Period Type:	duration

- Definition

Amount of cash outflow for principal payment on finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	credit
Period Type:	duration

- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

+ References

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- Definition

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

+ References

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- References

No definition available.

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- Definition

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

+ References

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-Publisher FASB
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- Definition

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

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

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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

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Balance Type:	na
Period Type:	instant

- Definition

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

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Balance Type:	debit
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- Definition

Amount of short-term lease cost, excluding expense for lease with term of one month or less.

+ References

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- Definition

Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

+ References

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