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Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Benefits paid |  | $ 2,565 | $ 2,341 |
Defined contribution plan, contribution amount |  | $ 1,378 | 1,109 | $ 925
Fixed Income [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target plan asset |  | 51.00% |  |
U.S. Equity [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target plan asset |  | 19.00% |  |
Non-U.S. Equity Securities [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target plan asset |  | 30.00% |  |
Defined Benefit Plan [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Accumulated benefit obligation |  | $ 103,736 | 83,724 |
Contributions for plan |  | 6,900 |  |
Net gains (losses) as a component of net periodic benefit cost |  | 0 |  |
Defined Benefit Plan [Member] | Subsequent Event [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Net gains (losses) as a component of net periodic benefit cost | $ 1,890 |  |  |
Supplemental Executive Retirement Plan [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Accumulated benefit obligation |  | 10,485 | 8,830 |
Benefits paid |  | 262 | 260 | 247
Net gains (losses) as a component of net periodic benefit cost |  | 0 |  |
Supplemental Executive Retirement Plan [Member] | Subsequent Event [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Net gains (losses) as a component of net periodic benefit cost | $ 112 |  |  |
Noncontributory Profit Sharing Program [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Contributions for plan |  | $ 6,841 | $ 6,810 | $ 5,799

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- Definition Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(4) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920 + Details
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- Definition Amount of contributions expected to be received by defined benefit plan from employer in fiscal year. Excludes contributions paid by employer in current fiscal year. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920 + Details
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- Definition Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(5) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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