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Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Guarantees |  |
Letters of credit | $ 1,830,902 | $ 1,796,647
Accrued expenses and other liabilities |  |
Guarantees |  |
Allowance for unfunded credit reserves | 12,900 | 12,400
Other Commitments |  |
Unfunded commitments in investments in qualified affordable housing partnerships, tax credit and other investments | 157,200 | 161,000
Single Family and Multi-family Residential | Loans Sold or Securitized with Recourse | Accrued expenses and other liabilities | Loans Sold or Securitized With Recourse |  |
Guarantees |  |
Allowance for unfunded credit reserves | 88 | $ 123
Standby Letters of Credit |  |
Guarantees |  |
Letters of credit | 1,770,000 |
Commercial Letters of Credit |  |
Guarantees |  |
Letters of credit | $ 62,000 |

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- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions. + References No definition available. + Details
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