Schedule I - CONDENSED BALANCE SHEETS (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Assets
Cash and cash equivalents	$ 1,491	$ 2,558
Receivables, net	457	494	$ 167
Prepayments and other current assets	155	239
Total current assets	2,265	3,457
Deferred Tax Assets, Net, Noncurrent	10	2
Total assets	25,775	25,436
Liabilities and Stockholders’ Equity
Accounts payable	399	318
Accrued expenses and other current liabilities	1,217	1,326
Interest payable	56	38
Total current liabilities	2,000	1,884
Long-term debt	8,801	8,849
Deferred income taxes	730	577
Total liabilities	22,437	22,139
Total liabilities and stockholders’ equity	25,775	25,436
Parent Company [Member]
Assets
Cash and cash equivalents	457	926
Receivables, net	21	33
Prepayments and other current assets	5	5
Intercompany receivables	20	33
Total current assets	503	997
Deferred charges and other assets	128	147
Investment in subsidiary	4,199	4,434
Total assets	4,830	5,578
Liabilities and Stockholders’ Equity
Accounts payable	1	5
Accrued expenses and other current liabilities	7	13
Interest payable	14	13
Intercompany payables	20	64
Total current liabilities	42	95
Long-term debt	1,119	1,121
Deferred credits and other	419	1,136
Total liabilities	1,580	2,352
Total stockholders’ equity	3,250	3,226
Total liabilities and stockholders’ equity	$ 4,830	$ 5,578