Investments in Securities - Maturity Information (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Total Carrying Amount
Total Carrying Amount, Net	$ 711
Amortized cost, one year or less	1
Amortized cost, after one year through five years	20
Amortized cost, after five years through ten years	28
Amortized cost, after ten years	662
Total Fair Value
Total fair value	696	$ 837
Fair value, one year or less	1
Fair value, after one year through five years	20
Fair value, after five years through ten years	29
Fair value, after ten years	$ 646
Weighted average yield	7.27%
Weighted average yield, one year or less	7.68%
Weighted average yield, after one year through five years	6.80%
Weighted average yield, after five years through ten years	6.64%
Weighted average yield, after ten years	7.31%
Agency securities
Total Carrying Amount
Total Carrying Amount, Net	$ 445
Amortized cost, one year or less	0
Amortized cost, after one year through five years	3
Amortized cost, after five years through ten years	12
Amortized cost, after ten years	430
Total Fair Value
Total fair value	426	507
Fair value, one year or less	0
Fair value, after one year through five years	3
Fair value, after five years through ten years	12
Fair value, after ten years	411
Other mortgage-related securities
Total Carrying Amount
Total Carrying Amount, Net	266
Amortized cost, one year or less	1
Amortized cost, after one year through five years	17
Amortized cost, after five years through ten years	16
Amortized cost, after ten years	232
Total Fair Value
Total fair value	270	$ 330
Fair value, one year or less	1
Fair value, after one year through five years	17
Fair value, after five years through ten years	17
Fair value, after ten years	$ 235