Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Consolidated Balance Sheets
Payables due to affiliates	$ 14	$ 20
Deferred revenue to affiliates	$ 32	$ 31
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, authorized shares	1,250,000	1,250,000
Common stock, issued shares	1,164,848	1,169,217
Common stock, outstanding shares	1,164,848	1,169,217