Mortgage Loans (Mortgage Loans Held For Portfolio by Collateral or Guarantee Type) (Details) - Residential Portfolio Segment [Member] - USD ($) $ in Thousands |
Jun. 30, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Residential Mortgage Loans [Line Items] | ||
| Total unpaid principal balance | $ 9,111,594 | $ 8,877,927 |
| Government Loans [Member] | ||
| Residential Mortgage Loans [Line Items] | ||
| Total unpaid principal balance | 320,477 | 324,409 |
| Conventional Loans [Member] | ||
| Residential Mortgage Loans [Line Items] | ||
| Total unpaid principal balance | $ 8,791,117 | $ 8,553,518 |