Income Taxes Operating Loss Carryforwards (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
U.K.
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 41	$ 266
Capital loss carryforwards	573	577
Interest carryforwards	0	121
U.S. Federal
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	25	49
Capital loss carryforwards	112	112
Interest carryforwards	1,140	1,220
U.S. State
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	398	378
Capital loss carryforwards	123	123
Interest carryforwards	551	573
Other
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	301	400
Capital loss carryforwards	35	42
Interest carryforwards	26	34
Other carryforwards	$ 5	$ 0