Summary of Significant Accounting Policies - Retirement Benefits (Details) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2023 |
Dec. 31, 2022 |
Dec. 31, 2021 |
|
| Summary of Significant Accounting Policies | |||
| Pension contributions | $ 2,628,000 | $ 2,810,000 | $ 2,505,000 |
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of cost for defined contribution plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|