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Employee Benefits - Additional Information (Details) | 12 Months Ended
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Dec. 31, 2021 USD ($) d plan yr Component | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |
Number of company contribution components, Retirement Savings Plan | Component | 3 |  |
Fixed percentage of employer's contribution based on eligible compensation | 3.00% |  |
Employee contribution limit per calendar year (as a percent of compensation) | 50.00% |  |
Employer match of employee contributions up to 2% of eligible compensation | 1.25% |  |
Percentage of eligible compensation, matched $1.25 for by employer for each dollar amount contributed by participants | 2.00% |  |
Employer match of employee contributions over 2% up to 5% of eligible compensation | $ 0.50 |  |
Employee's contribution matched by employer (in dollars) | $ 1.00 |  |
Percentage of eligible compensation, matched $0.50 for by employer for each dollar amount contributed by participants, low end of range | 2.00% |  |
Percentage of eligible compensation, matched $0.50 for by employer for each dollar amount contributed by participants, high end of range | 5.00% |  |
Total expense for all components of the company's defined contribution plans | $ 16,000,000.0 | $ 14,000,000.0 | $ 15,200,000
Effect of market fluctuations in cash flow on target allocation limits (as a percent) | 5.00% |  |
Period during which asset allocation is expected to conform to range limits (in days) | d | 90 |  |
Minimum [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fixed income securities, percentage of variable component in strategic targets (as a percent) | 10.00% |  |
Maximum |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fixed income securities, percentage of variable component in strategic targets (as a percent) | 20.00% |  |
Equity Securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Target plan asset allocations | 60.00% |  |
Fixed Income Securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Target plan asset allocations | 40.00% |  |
Cash | Minimum [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Effect of market fluctuations in cash flow on target allocation limits (as a percent) | 0.00% |  |
Cash | Maximum |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Effect of market fluctuations in cash flow on target allocation limits (as a percent) | 20.00% |  |
Equity Securities, Domestic | Minimum [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Target plan asset allocations | 50.00% |  |
Equity Securities, Domestic | Maximum |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Target plan asset allocations | 100.00% |  |
Equity Securities, International | Minimum [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Target plan asset allocations | 0.00% |  |
Equity Securities, International | Maximum |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Target plan asset allocations | 50.00% |  |
S&P 500 Index |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Performance benchmark (as a percent) | 36.00% |  |
MSCI EAFE Index |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Performance benchmark (as a percent) | 24.00% |  |
Barclays Capital Aggregate Bond Index |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Performance benchmark (as a percent) | 40.00% |  |
Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Number of defined benefit plans | plan | 2 |  |
Actuarial Losses (Gains) | $ 2,817,000 | (10,364,000) |
Expected future employer contributions, next fiscal year | 400,000 |  |
Pension Benefits | Excess Retirement Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Accumulated benefit obligation | $ 3,300,000 | 3,600,000 |
Postretirement Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Retirees' age and above which Medicare supplemental plan subsidy is provided (in years) | yr | 65 |  |
Limit on annual credit provided in HRA to eligible employees | $ 1,200,000 |  |
Actuarial Losses (Gains) | $ 2,514,000 | (3,559,000) |
Ultimate health care cost trend rate (as a percent) | 4.00% |  |
Ultimate health care cost trend rate period | 2045 |  |
Expected future employer contributions, next fiscal year | $ 1,400,000 |  |
Other Pension Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Actuarial Losses (Gains) | (4,300,000) | (9,300,000) |
Postemployment Retirement Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Actuarial Losses (Gains) | $ (1,300,000) | $ (2,900,000) |

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