Consolidated Balance Sheets Consolidated Balance Sheets Parentheticals - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Cash and cash equivalents ($43 and $39 attributable to VIEs)	$ 205	$ 284
Accounts receivable, net of allowance of $9 and $9	9	9
Restricted cash, current ($90 and $74 attributable to VIEs)	167	134
Property, plant and equipment, net ($3,919 and $4,048 attributable to VIEs)	12,442	12,724
Restricted cash, net of current portion ($33 and $24 attributable to VIEs)	34	25
Other assets ($30 and $22 attributable to VIEs)	277	320
Debt, current portion ($201 and $175 attributable to VIEs)	637	225
Debt, net of current portion ($1,978 and $2,238 attributable to VIEs)	$ 10,148	$ 11,180
Common Stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common Stock, authorized shares (in shares)	5,000	1,400,000,000
Common Stock, issued shares (in shares)	105.2	361,677,891
Common Stock, outstanding shares (in shares)	105.2	360,516,091
Treasury Stock, shares (in shares)	0	1,161,800
Variable Interest Entity, Primary Beneficiary [Member]
Cash and cash equivalents ($43 and $39 attributable to VIEs)	$ 43	$ 39
Restricted cash, current ($90 and $74 attributable to VIEs)	90	74
Property, plant and equipment, net ($3,919 and $4,048 attributable to VIEs)	3,919	4,048
Restricted cash, net of current portion ($33 and $24 attributable to VIEs)	33	24
Other assets ($30 and $22 attributable to VIEs)	30	22
Debt, current portion ($201 and $175 attributable to VIEs)	201	175
Debt, net of current portion ($1,978 and $2,238 attributable to VIEs)	$ 1,978	$ 2,238