Income Taxes - Deferred Income Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets
Net operating loss carryforward - US	$ 371	$ 968
Net operating loss carryforward - Non-US	178	167
Market value difference of loan portfolio	310	23
Accruals	115	104
Tax credits	839	806
Other	185	151
Total deferred tax assets before valuation allowance	1,998	2,219
Less: valuation allowance	(279)	(270)
Total deferred tax assets	1,719	1,949
Deferred tax liabilities
Depreciable assets	2,177	2,020
Deferred acquisition costs	123	134
Other	152	103
Total deferred tax liabilities	2,452	2,257
Net deferred tax liability	(733)	$ (308)
Tax Year 2039 [Member]
Deferred tax assets
Net operating loss carryforward - US	339
Net operating loss carryforward - Non-US	142
Tax credits	839
Expiring Indefinitely [Member]
Deferred tax assets
Net operating loss carryforward - US	32
Net operating loss carryforward - Non-US	$ 36