BORROWINGS - 2030, 2029, 2028, 2027, 2026, 2025 and 2024 Notes (Details)									1 Months Ended		12 Months Ended
	Mar. 19, 2025 USD ($) investor	Dec. 11, 2024	Sep. 16, 2024 USD ($)	May 30, 2024 USD ($)	Aug. 31, 2023 USD ($)	Jan. 23, 2023 USD ($)	Dec. 29, 2021 USD ($)	Jul. 25, 2019 USD ($)	Jan. 31, 2021 USD ($)	Aug. 31, 2019 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2021 USD ($)	Oct. 21, 2025 USD ($)	Sep. 22, 2025	Jun. 30, 2025	Mar. 31, 2022 USD ($)	May 20, 2021 USD ($)	Feb. 16, 2021 USD ($)
Debt Instrument [Line Items]
Interest rate											7.53%	7.22%
Aggregate principal amount											$ 819,888,000	$ 708,041,000
Loss on extinguishment of debt											179,000	0	$ 271,000
Medium-term Notes
Debt Instrument [Line Items]
Interest expense											56,636,000	52,423,000	51,890,000
2030 8.375% Notes
Debt Instrument [Line Items]
Proceeds from Notes											32,000,000	0	0
2030 8.375% Notes | Medium-term Notes
Debt Instrument [Line Items]
Loans	$ 30,000,000.0										$ 52,000,000	$ 0			$ 2,000,000.0
Number of accredited investors | investor	11
Percent of principal amount	100.00%
Interest rate											8.375%	0.00%
Proceeds from Notes	$ 29,250,000
Interest expense											$ 2,400,000	$ 0	0
Aggregate principal amount											51,391,000	0
2029 8.50% Notes
Debt Instrument [Line Items]
Proceeds from Notes											0	71,875,000	0
2029 8.50% Notes | Medium-term Notes
Debt Instrument [Line Items]
Loans				$ 71,900,000							$ 71,808,000	$ 71,875,000
Interest rate				8.50%							8.50%	8.50%				8.50%
Interest expense											$ 6,600,000	$ 3,900,000	0
Additional principal purchased				$ 9,400,000
Proceeds before expenses				$ 69,600,000
Aggregate principal amount											70,066,000	69,622,000
2029 8.625% Notes
Debt Instrument [Line Items]
Proceeds from Notes											0	75,000,000	0
2029 8.625% Notes | Medium-term Notes
Debt Instrument [Line Items]
Loans			$ 75,000,000.0								$ 75,000,000	$ 75,000,000
Interest rate			8.625%								8.625%	8.625%
Interest expense											$ 7,000,000.0	$ 2,000,000.0	0
Proceeds before expenses			$ 72,800,000
Aggregate principal amount											73,150,000	72,662,000
2028 Notes (8.00%)
Debt Instrument [Line Items]
Proceeds from Notes											0	0	40,000,000
2028 Notes (8.00%) | Medium-term Notes
Debt Instrument [Line Items]
Loans					$ 40,000,000.0						$ 40,000,000	$ 40,000,000
Interest rate					8.00%						8.00%	8.00%
Interest expense											$ 3,500,000	$ 3,500,000	1,200,000
Additional principal purchased					$ 5,000,000.0
Proceeds before expenses					$ 38,000,000.0
Aggregate principal amount											39,073,000	38,726,000
2025 8.13% Notes
Debt Instrument [Line Items]
Proceeds from Notes											$ 0	$ 0	50,000,000
Interest expense													4,300,000
2025 8.13% Notes | Medium-term Notes
Debt Instrument [Line Items]
Loans						$ 50,000,000.0
Percent of principal amount		100.00%
Interest rate		8.125%				8.125%					8.125%	8.125%
Interest expense											$ 4,100,000	$ 4,600,000	0
Net proceeds						$ 48,940,000
2026 Notes | Medium-term Notes
Debt Instrument [Line Items]
Loans									$ 115,000,000.0		$ 95,000,000	$ 115,000,000			$ 20,000,000.0
Interest rate									5.50%		5.50%	5.50%
Interest expense											$ 6,800,000	$ 7,000,000.0	7,000,000.0
Net proceeds									$ 111,300,000
Aggregate principal amount											95,000,000	114,282,000
2026 Notes, Overallotment Option | Medium-term Notes
Debt Instrument [Line Items]
Loans									$ 15,000,000.0
2025 5.00% Notes | Medium-term Notes
Debt Instrument [Line Items]
Loans											$ 0	$ 30,000,000						$ 15,000,000.0
Interest rate											5.00%	5.00%					5.00%	5.00%
Interest expense											$ 500,000	$ 1,900,000	1,800,000
Additional principal issuable																		$ 15,000,000.0
Aggregate principal amount											0	29,913,000
2024 Notes | Medium-term Notes
Debt Instrument [Line Items]
Loans								$ 55,000,000.0											$ 10,000,000.0	$ 5,000,000.0
Percent of principal amount							100.00%
Interest rate								5.75%
Interest expense											$ 0	$ 1,400,000	$ 2,400,000
Additional principal purchased										$ 8,250,000
Net proceeds								$ 53,300,000		$ 8,000,000.0
Principal redeemed							$ 40,000,000.0
Aggregate principal amount							$ 78,250,000
Redemption price per note							25
Loss on extinguishment of debt														$ 600,000