Derivatives - Gains and Losses on Fair Value Hedge (Details) - USD ($)
$ in Millions |
12 Months Ended |
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Interest Income, Mortgage Loans |
$ 68,583
|
$ 66,037
|
$ 63,735
|
| Interest Expense |
(61,047)
|
(58,033)
|
(53,643)
|
| Other income (loss) |
323
|
762
|
4,984
|
| Interest rate risk on held-for-investment mortgage loan [Member] | Interest income |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge |
4,569
|
(1,776)
|
(107)
|
| Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments |
(4,309)
|
1,091
|
313
|
| Interest accrual on fair value hedging derivatives for held-for-investment loan |
(48)
|
(439)
|
(83)
|
| Discontinued hedge related basis adjustment amortization |
(446)
|
133
|
(16)
|
| Interest rate risk on held-for-investment mortgage loan [Member] | Other income (loss) |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge |
|
|
351
|
| Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments |
|
|
(215)
|
| Interest accrual on fair value hedging derivatives for held-for-investment loan |
|
|
0
|
| Discontinued hedge related basis adjustment amortization |
|
|
0
|
| Interest rate risk on held-for-investment mortgage loan [Member] | Gain (Loss) on Derivative Instruments [Member] |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Interest accrual on fair value hedging derivatives for held-for-investment loan |
|
|
(277)
|
| Interest rate risk on debt [Member] [Member] | Interest expense |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge |
(1,038)
|
145
|
93
|
| Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments |
1,231
|
155
|
(53)
|
| Discontinued hedge related basis adjustment amortization |
63
|
(3)
|
0
|
| Interest accruals on fair value hedging derivatives for debt |
$ (184)
|
$ (313)
|
$ 8
|