Goodwill and Other Intangible Assets (Details) - Other Intangible Assets - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Other intangible assets by major asset class
Intangible assets subject to amortization, gross carrying amount	$ 302		$ 302		$ 304
Intangible assets subject to amortization, accumulated amortization	210		210		200
Intangible assets subject to amortization, net	92		92		104
Intangible assets not subject to amortization	226		226		226
Total other intangible assets, gross carrying amount	528		528		530
Total other intangible assets, net	318		318		330
Amortization expense of intangible assets	4	$ 4	11	$ 12
Estimated intangible asset amortization expense, remainder of 2020	4		4
Estimated intangible asset amortization expense, 2021	14		14
Estimated intangible asset amortization expense, 2022	13		13
Estimated intangible asset amortization expense, 2023	12		12
Estimated intangible asset amortization expense, 2024	12		12
Customer-related [Member]
Other intangible assets by major asset class
Intangible assets subject to amortization, gross carrying amount	98		98		99
Intangible assets subject to amortization, accumulated amortization	28		28		21
Intangible assets subject to amortization, net	70		70		78
Contract-based [Member]
Other intangible assets by major asset class
Intangible assets subject to amortization, gross carrying amount	204		204		205
Intangible assets subject to amortization, accumulated amortization	182		182		179
Intangible assets subject to amortization, net	22		22		$ 26
Insurance Contracts Acquired in Business Combination [Member]
Other intangible assets by major asset class
Estimated intangible asset amortization expense, remainder of 2020	1		1
Estimated intangible asset amortization expense, 2021	4		4
Estimated intangible asset amortization expense, 2022	3		3
Estimated intangible asset amortization expense, 2023	3		3
Estimated intangible asset amortization expense, 2024	$ 2		$ 2