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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, 2018
Debt Instrument [Line Items] |
Schedule of Maturities of Long-term Debt | At December 31, 2018, 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 |  | 2.64 | % |  | $ | 392,000 |
Over 1 through 5 years |  | 3.85 | % |  | 2,000 |
Due after 10 years |  | 5.37 | % |  | 5,000 |
Total |  | 399,000 |
Valuation adjustment from acquisition accounting |  | 523 |
Total |  | $ | 399,523 |
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, 2018, 2017 and 2016:
|  | Years ended December 31,
|  | 2018 |  | 2017 |  | 2016
|  | (dollars in thousands)
Balance at end of period |  | $ | 399,523 |  |  | $ | 11,579 |  |  | $ | 6,493 |
Average balance during period |  | $ | 166,563 |  |  | $ | 79,788 |  |  | $ | 79,673 |
Maximum month-end balance during period |  | $ | 399,523 |  |  | $ | 317,480 |  |  | $ | 250,515 |
Weighted average rate during period |  | 2.29 | % |  | 1.33 | % |  | 0.80 | %
Weighted average rate at December 31 |  | 2.68 | % |  | 4.08 | % |  | 5.42 | %
Schedule of Financial Instruments Owned and Pledged as Collateral |

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- Definition Tabular disclosure of financial instruments held by the entity for its own account for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions. Description may include equity, fixed income, debt or other securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729 + Details
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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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