Income Taxes - Deferred Income Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets
Net operating loss carryforward - US	$ 1,049	$ 409
Net operating loss carryforward - Non-US	202	189
Market value difference of loan portfolio	105	166
Accruals	135	107
Tax Credits	388	131
Other	113	113
Total deferred tax assets before valuation allowance	1,992	1,115
Less: valuation allowance	(166)	(104)
Total deferred tax assets	1,826	1,011
Deferred tax liabilities
Depreciable assets	1,470	645
Deferred acquisition costs	183	116
Other	119	148
Total deferred tax liabilities	1,772	909
Net deferred tax asset	$ 54	$ 102