Fair Value Measurements - Principal Amount And Estimated Fair Value Of Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value Measurements
Principal Amount	$ 372,779	$ 270,913
2023 Notes (mature September 2023)
Fair Value Measurements
Principal Amount		30,000
Fair Value		31,149
2026 Notes (mature February 2026)
Fair Value Measurements
Principal Amount	40,199	200,000
Fair Value	64,117	277,014
MARAD Debt (matures February 2027)
Fair Value Measurements
Principal Amount	32,580	40,913
Fair Value	32,348	40,940
2029 Notes (mature March 2029)
Fair Value Measurements
Principal Amount	300,000
Fair Value	315,987
Total Debt
Fair Value Measurements
Principal Amount	372,779	270,913
Fair Value	$ 412,452	$ 349,103