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Debt Obligations - Senior Unsecured Notes (Details) - USD ($) $ in Thousands	1 Months Ended			12 Months Ended
	Oct. 31, 2024	May 31, 2023	Mar. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Apr. 30, 2024	Apr. 30, 2023
Debt Instrument [Line Items]
Debt, Wtd. Avg. Rate				6.86%	7.67%
Outstanding principal balance repaid				$ 26,600	$ 43,100
9.00% Notes
Debt Instrument [Line Items]
Interest rate				9.00%
Debt, face value				$ 100,000	0
Carrying value				$ 98,352	$ 0
Debt, Wtd. Avg. Rate				9.00%	0.00%
7.75% Notes
Debt Instrument [Line Items]
Interest rate				7.75%
Debt, face value				$ 95,000	$ 95,000
Carrying value				$ 94,275	$ 93,697
Debt, Wtd. Avg. Rate				7.75%	7.75%
8.50% Notes
Debt Instrument [Line Items]
Interest rate				8.50%		8.50%
Debt, face value				$ 150,000	$ 150,000	$ 150,000
Carrying value				$ 148,531	$ 148,023
Debt, Wtd. Avg. Rate				8.50%	8.50%
Proceeds from issued debt						$ 147,500
5.00% Notes
Debt Instrument [Line Items]
Interest rate				5.00%			5.00%
Debt, face value				$ 180,000	$ 180,000		$ 180,000
Carrying value				$ 178,300	$ 177,875
Debt, Wtd. Avg. Rate				5.00%	5.00%
Proceeds from issued debt							$ 177,200
4.50% Notes
Debt Instrument [Line Items]
Interest rate				4.50%			4.50%	4.50%
Debt, face value				$ 270,000	$ 270,000		$ 270,000	$ 275,000
Carrying value				$ 268,601	$ 267,763
Debt, Wtd. Avg. Rate				4.50%	4.50%
Proceeds from issued debt							$ 265,800	$ 271,800
5.00% Notes
Debt Instrument [Line Items]
Interest rate				5.00%			5.00%
Debt, face value				$ 175,000	$ 175,000		$ 175,000
Carrying value				$ 174,161	$ 173,542
Debt, Wtd. Avg. Rate				5.00%	5.00%
Proceeds from issued debt							$ 172,300
4.50% Notes
Debt Instrument [Line Items]
Interest rate				4.50%
Debt, face value				$ 275,000	$ 275,000
Carrying value				$ 273,927	$ 273,444
Debt, Wtd. Avg. Rate				4.50%	4.50%
4.75% Notes
Debt Instrument [Line Items]
Interest rate				4.75%
Debt, face value				$ 0	$ 110,000
Carrying value				$ 0	$ 109,721
Debt, Wtd. Avg. Rate				0.00%	4.75%
Redemption of aggregate principal amount (as a percent)				100.00%
5.75% Notes
Debt Instrument [Line Items]
Interest rate				5.75%					5.75%
Debt, face value				$ 0	$ 90,000				$ 90,000
Carrying value				$ 0	$ 89,903
Debt, Wtd. Avg. Rate				0.00%	5.75%
Senior unsecured notes
Debt Instrument [Line Items]
Debt, face value				$ 1,245,000	$ 1,345,000
Carrying value				$ 1,236,147	$ 1,333,968
Debt, Wtd. Avg. Rate				5.73%	5.41%
Deferred financing fees				$ 8,900	$ 11,000
Luxembourg Debt Fund
Debt Instrument [Line Items]
Weighted average note rate including certain fees and costs (as a percent)				6.02%	5.70%
Senior Unsecured Notes 9.00 Percent \| Senior unsecured notes
Debt Instrument [Line Items]
Interest rate	9.00%
Debt, face value	$ 100,000
Proceeds from issuance of debt	$ 98,400
7.75% senior unsecured notes
Debt Instrument [Line Items]
Interest rate			7.75%
Carrying value			$ 95,000
Senior Unsecured Notes
Debt Instrument [Line Items]
Interest rate			8.00%
Proceeds from issuance of unsecured notes			$ 93,400
Amount utilized from proceeds of issuance of unsecured note			$ 70,800
5.625% Notes
Debt Instrument [Line Items]
Interest rate		5.625%				5.625%
Proceeds from issuance of unsecured notes						$ 47,500
Proceeds from issued debt		$ 78,800
8.00% Notes
Debt Instrument [Line Items]
Interest rate										8.00%
Debt, face value										$ 70,800
4.75% Notes
Debt Instrument [Line Items]
Interest rate	4.75%					4.75%
Debt, face value	$ 110,000					$ 66,100