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Other Borrowed Funds (Tables) | 12 Months Ended
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Dec. 31, 2019
Schedule of other borrowed funds | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | December 31, |
​ | ​ | 2019 | ​ | 2018 |
​ | ​ | (Dollars in Thousands) |
Federal Home Loan Bank advances—short-term |  | ​ |  |  | ​ |  | ​
Balance at year end | ​ | $ | 190,000 | ​ | $ | 268,975 | ​
Rate on balance outstanding at year end | ​ |  | 1.48 | % |  | 2.70 | %
Average daily balance | ​ | $ | 190,431 | ​ | $ | 621,357 | ​
Average rate | ​ |  | 2.60 | % |  | 1.97 | %
Maximum amount outstanding at any month end | ​ | $ | 371,775 | ​ | $ | 1,007,100 | ​
Federal Home Loan Bank advances—long-term(1) | ​ | ​ | ​ | ​ | ​ | ​ | ​
Balance at year end | ​ | $ | 436,511 | ​ | $ | 436,690 | ​
Rate on balance outstanding at year end | ​ |  | 1.73 | % |  | 1.73 | %
Average daily balance | ​ | $ | 436,593 | ​ | $ | 302,373 | ​
Average rate | ​ |  | 1.71 | % |  | 1.71 | %
Maximum amount outstanding at any month end | ​ | $ | 436,675 | ​ | $ | 436,700 | ​
​
| (1) | Long-term advances at December 31, 2019 and December 31, 2018 consisted of both amortizing and non-amortizing advances. The non-amortizing advances mature in the following increments: $75,000,000 in July 2028, $100,000,000 in March 2033 and $250,000,000 in August 2033 and are callable by the FHLB on a quarterly basis. Two amortizing advances are outstanding at December 31, 2019 in the amounts of $3,146,000 and $8,365,000 and mature in December 2033 and November 2033, respectively. The amortization on the amortizing long-term advances totals approximately $179,000 per year for each of the next five years.

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- Definition Tabular disclosure of all borrowed funds not defined anywhere else in the taxonomy. Includes Federal Home Loan Bank borrowings, which are short and long-term fixed borrowings. + References No definition available. + Details
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