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Employee Benefit Plans - Schedule of fair values of plan assets (Detail) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets, fair value | $ 96,975 | $ 93,809 | $ 70,900
Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets, fair value | 14,059 | 21,707 |
Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets, fair value | 82,916 | 72,102 |
Fair Value, Inputs, Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets, fair value | 0 | 0 |
Cash |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets, fair value | 14,059 | 21,707 |
Cash | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets, fair value | 14,059 | 21,707 |
Cash | Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets, fair value | 0 | 0 |
Cash | Fair Value, Inputs, Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets, fair value | 0 | 0 |
Fixed Income Securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets, fair value | $ 80,612 | 63,444 |
Investment in funds (in percentage) | 100.00% |  |
Fixed Income Securities | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets, fair value | $ 0 | 0 |
Fixed Income Securities | Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets, fair value | 80,612 | 63,444 |
Fixed Income Securities | Fair Value, Inputs, Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets, fair value | 0 | 0 |
Other Securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets, fair value | 2,304 | 8,658 |
Other Securities | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets, fair value | 0 | 0 |
Other Securities | Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets, fair value | 2,304 | 8,658 |
Other Securities | Fair Value, Inputs, Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets, fair value | $ 0 | $ 0 |

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- Definition Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee. + 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 (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 4: 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=123450688&loc=d3e4179-114921 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(02) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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