Organization and Basis of Presentation (Details) T in Millions, MW in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019 USD ($) MW T Facility	Mar. 31, 2018 USD ($)	Jan. 01, 2019 USD ($)	Dec. 31, 2018 USD ($)	Jan. 01, 2018 USD ($)	Dec. 31, 2017 USD ($)
Organization And Summary Of Significant Accounting Policies [Line Items]
Accumulated deficit	$ (365)			$ (334)
Right of use asset	55
Lease liability	$ 60
Solid waste processed (in tons) | T	22
Number Of Energy From Waste Facilities | Facility	43
Annual Output | MW	10
Intangible assets, net	$ 274			279
Accumulated Other Comprehensive Income (Loss), Net of Tax					$ 1
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract]
Cash and cash equivalents	88	$ 51		58
Restricted funds held in trust- short term	31	42		39
Restricted funds held in trust- long term	7	23		8
Beginning of period balance presented in the statement of cash flows	126	116		$ 105		$ 194
Statement of Cash Flows [Abstract]
Cash provided by operating activities	37	3
Cash used in investing activities	(27)	26
Cash provided by financing activities	$ 11	$ (110)
Accounting Standards Update 2018-02 [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax			$ 0
Accounting Standards Update 2016-02 [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Right of use asset			57
Lease liability			62
Retained Earnings, Unappropriated [Member] | Accounting Standards Update 2018-02 [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax			$ 2