Fair Value Measurements - Principal Amount And Estimated Fair Value Of Long-Term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Dec. 01, 2023
Fair Value Measurements
Principal Amount	$ 328,258	$ 372,779
Fair Value	345,906	412,452
2026 Notes (fully redeemed March 2024)
Fair Value Measurements
Principal Amount		40,199
Fair Value		64,117
MARAD Debt (matures February 2027)
Fair Value Measurements
Principal Amount	28,258	32,580
Fair Value	27,906	32,348
2029 Notes (mature March 2029)
Fair Value Measurements
Principal Amount	300,000	300,000	$ 300,000
Fair Value	$ 318,000	$ 315,987

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-4

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant