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Federal Home Loan Bank and Federal Reserve Bank Borrowings (Tables) - Federal Home Loan Bank Advances [Member] | 12 Months Ended
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Dec. 31, 2019
Debt Instrument [Line Items] |
Schedule of Maturities of Long-term Debt | At December 31, 2019, FHLB advances were scheduled to mature as follows:
|  | Federal Home Loan Bank Advances Fixed rate advances
|  | Weighted Average Rate |  | Amount
|  | (dollars in thousands)
Within 1 year |  | 1.82 | % |  | $ | 946,000 |
Over 1 through 5 years |  | 3.85 | % |  | 2,000 |
Due after 10 years |  | 5.37 | % |  | 5,000 |
Total |  | 953,000 |
Valuation adjustment from acquisition accounting |  | 469 |
Total |  | $ | 953,469 |
Debt Instrument Activity For Year | The maximum, average outstanding and year end balances and average interest rates on advances from the FHLB were as follows for the years ended December 31, 2019, 2018 and 2017:
|  | Years ended December 31,
|  | 2019 |  | 2018 |  | 2017
|  | (dollars in thousands)
Balance at end of period |  | $ | 953,469 |  |  | $ | 399,523 |  |  | $ | 11,579 |
Average balance during period |  | $ | 469,983 |  |  | $ | 166,563 |  |  | $ | 79,788 |
Maximum month end balance during period |  | $ | 953,469 |  |  | $ | 399,523 |  |  | $ | 317,480 |
Weighted average rate during period |  | 2.42 | % |  | 2.29 | % |  | 1.33 | %
Weighted average rate at December 31 |  | 1.84 | % |  | 2.68 | % |  | 4.08 | %

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- Definition Tabular disclosure of the combined aggregate amount of maturities and sinking fund requirements for all long-term borrowings for each of the five years following the date of the latest balance sheet date presented. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 + Details
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