Collateral and Offsetting of Assets and Liabilities - Underlying Collateral Pledged (Details) - USD ($)
$ in Millions |
Dec. 31, 2019 |
Dec. 31, 2018 |
| Collateral in the Form of Securities Pledged [Line Items] |
|
|
| Securities pledged with the ability for the secured party to repledge |
$ 13,131
|
$ 8,802
|
| Securities Sold under Agreements to Repurchase |
|
|
| Collateral in the Form of Securities Pledged [Line Items] |
|
|
| Securities pledged with the ability for the secured party to repledge |
9,346
|
$ 6,027
|
| Securities Sold under Agreements to Repurchase | Overnight and continuous |
|
|
| Collateral in the Form of Securities Pledged [Line Items] |
|
|
| Securities pledged with the ability for the secured party to repledge |
0
|
|
| Securities Sold under Agreements to Repurchase | 30 days or less |
|
|
| Collateral in the Form of Securities Pledged [Line Items] |
|
|
| Securities pledged with the ability for the secured party to repledge |
9,081
|
|
| Securities Sold under Agreements to Repurchase | After 30 days through 90 days |
|
|
| Collateral in the Form of Securities Pledged [Line Items] |
|
|
| Securities pledged with the ability for the secured party to repledge |
265
|
|
| Securities Sold under Agreements to Repurchase | Greater than 90 days |
|
|
| Collateral in the Form of Securities Pledged [Line Items] |
|
|
| Securities pledged with the ability for the secured party to repledge |
$ 0
|
|