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Employee Benefits - Retirement plan contribution (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Employee Benefits |  |  |
Retirement plan contributions | $ 5,080 | $ 5,137 | $ 5,126
Total ESOP shares outstanding | 1,111,424 | 1,207,952 | 1,170,611
Salary Reduction Plan |  |  |
Employee Benefits |  |  |
Retirement plan contributions | $ 3,148 | $ 3,123 | $ 2,960
ESOP |  |  |
Employee Benefits |  |  |
Retirement plan contributions | $ 1,932 | $ 2,014 | $ 2,166

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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 Amount of cost for defined contribution plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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- Definition Sum of the allocated, committed-to-be-released and suspense shares of the entity held by the plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 40 -Section 50 -Paragraph 1 -Subparagraph (d) -URI https://asc.fasb.org/extlink&oid=109244661&loc=d3e17540-113929 + Details
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