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Share-Based Compensation - Performance Restricted Stock Units - Narrative (Details) - PRSUs shares in Thousands, $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2024 USD ($) shares	Mar. 31, 2023 USD ($) shares	Dec. 31, 2023 metric shares	Dec. 31, 2022 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units increased (decreased) during the period (in shares) | shares	32
Recognized share-based compensation expense (benefit) | $	$ 0.1	$ 0.7
Unrecognized compensation cost | $	$ 2.4
Nonvested shares outstanding (in shares) | shares	309	382	60	280
Weighted-average period over which unrecognized compensation cost is expected to be recognized (years)	3 years
Executive and Senior Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period (years)	1 year
Vesting period	4 years
Requisite service period	5 years
Executive and Senior Officers | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage, range of target award	0.00%
Executive and Senior Officers | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage, range of target award	200.00%
Executive Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
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