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Interest Expense (Narrative) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021 | Dec. 31, 2021
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage | 4.20% |  | 4.20% |  |
Repayments of Long-term Debt |  |  | $ 110,000 | $ 200,000 |
Accretion of original issue discount on 2018 Term Loan Facility | $ 338 | $ 572 | 865 | 1,843 |
Amortization of debt issuance costs and modification costs | $ 932 | 1,337 | $ 2,176 | 5,368 |
2018 Term Loan Facility |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage | 4.67% |  | 4.67% |  | 3.50%
Repayments of Long-term Debt | $ 40,000 | 50,000 | $ 110,000 | 200,000 |
Accretion of original issue discount on 2018 Term Loan Facility | 200 | 300 | 500 | 1,200 |
Amortization of debt issuance costs and modification costs | $ 300 | $ 400 | $ 800 | 2,000 |
Payments of Debt Restructuring Costs |  |  |  | $ 1,600 |
2020 Senior Secured Notes |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 4.625% |  | 4.625% |  |

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