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Debt - Narrative (Details) |  | 3 Months Ended | 9 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2021 USD ($) entity | Sep. 30, 2021 USD ($) entity loan | Jun. 30, 2021 USD ($) | Mar. 31, 2021 USD ($) | Sep. 30, 2020 USD ($) | Jun. 30, 2020 USD ($) entity loan | Sep. 30, 2021 USD ($) entity loan | Sep. 30, 2020 USD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Oct. 02, 2019 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt | $ 326,286,000 | $ 326,286,000 |  |  |  |  | $ 326,286,000 |  |  |  |  |  | $ 375,397,000 |
Amortization of debt issuance costs |  | 492,000 |  |  | $ 727,000 |  | 1,756,000 | $ 2,219,000 |  |  |  |  |  |
Gain (loss) on extinguishment of debt |  | $ 968,000 |  |  | $ 0 |  | $ 2,032,000 | $ 0 |  |  |  |  |  |
Number of entities | entity | 2 | 2 |  |  |  | 2 | 2 |  |  |  |  |  |  |
Ownership interest in subsidiaries | 50.00% | 50.00% |  |  |  | 50.00% | 50.00% |  |  |  |  |  |  |
Paycheck protection loans received, CARES Act | loan |  |  |  |  |  | 3 |  |  |  |  |  |  |  |
Paycheck protection program loan amount, CARES Act |  |  |  |  |  | $ 9,800,000 |  |  |  |  |  |  |  |
Loans the SBA forgave, CARES Act | loan |  | 1 |  |  |  |  | 2 |  |  |  |  |  |  |
Credit Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash flow prepayment term |  |  |  |  |  |  | 5 days |  |  |  |  |  |  |
Term Loan Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (loss) on extinguishment of debt |  | $ 0 |  |  |  |  | $ (431,000) |  |  |  |  |  |  |
Paycheck Protection Program |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (loss) on extinguishment of debt |  | 968,000 |  |  |  |  | 2,463,000 |  |  |  |  |  |  |
Loan amount forgiven |  | $ 2,000,000 |  |  |  |  | $ 5,000,000 |  |  |  |  |  |  |
Secured Debt | Credit Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument face amount |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 475,000,000
Secured Debt | Term Loan Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 5.15% | 5.15% |  |  |  |  | 5.15% |  |  |  |  |  |  |
Repayments of debt |  |  |  |  |  |  | $ 20,612,000 |  |  |  |  |  |  |
Excess cash flow payment |  |  |  | $ 18,000,000 |  |  | 18,000,000 |  |  |  |  |  |  |
Optional prepayment |  |  | $ 5,444,000 |  |  |  | 5,444,000 |  |  |  |  |  |  |
Long-term debt | $ 310,944,000 | $ 310,944,000 |  |  |  |  | 310,944,000 |  |  |  |  |  | $ 355,000,000 |
Line of Credit | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt | $ 0 | 0 |  |  |  |  | 0 |  |  |  |  |  |  |
Revolving Credit Facility | Secured Debt | Term Loan Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument face amount |  |  |  |  |  |  |  |  |  |  |  |  |  | 400,000,000
Revolving Credit Facility | Line of Credit | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of credit, maximum borrowing capacity |  |  |  |  |  |  |  |  |  |  |  |  |  | 75,000,000
Debt instrument, LIBOR interest rate | 0.084% |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving Credit Facility | Line of Credit | Revolving Credit Facility | London Interbank Offered Rate (LIBOR) |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate | 2.50% |  |  |  |  |  |  |  |  |  |  |  |  |
Swing Line Loan | Line of Credit | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of credit, maximum borrowing capacity |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 15,000,000
Interest Rate Swap | Secured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivative, notional amount | $ 275,000,000 | $ 275,000,000 |  |  |  |  | $ 275,000,000 |  |  |  |  |  |  |
Forecast | Secured Debt | Term Loan Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Periodic payments |  |  |  |  |  |  |  |  | $ 18,300,000 | $ 22,300,000 | $ 16,200,000 | $ 24,700,000 |  |

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