Consolidated Statements of Shareholder's Equity - USD ($) $ in Millions	Total	Capital stock	Additional paid-in capital	Accumulated other comprehensive income	Retained earnings
Balance at Mar. 31, 2016	$ 9,397	$ 915	$ 2	$ 165	$ 8,315
Net income	358	0	0	0	358
Other comprehensive loss, net of tax	(162)	0	0	(162)	0
Balance at Dec. 31, 2016	9,593	915	2	3	8,673
Balance at Mar. 31, 2017	9,524	915	2	25	8,582
Net income	3,358	0	0	0	3,358
Other comprehensive loss, net of tax	(15)	0	0	(15)	0
Balance at Dec. 31, 2017	$ 12,867	$ 915	$ 2	$ 10	$ 11,940