Other assets and other liabilities (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Other assets:
Goodwill	$ 38,530	$ 38,530
Deferred loan exit fees	31,530	32,271
Accrued interest	64,439	64,504
Due from servicers	20,348	20,780
Intangible assets	18,072	17,749
PPP receivables	27,364	34,597
Receivable from third parties	34,187	36,519
Deferred financing costs	11,910	9,544
Deferred tax asset	21,085
Right-of-use assets	$ 4,297	$ 2,539
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Total other assets	Total other assets
Investments held to maturity	$ 3,446	$ 3,446
Purchased future receivables, net	3,717	9,483
Other assets	36,847	30,213
Total other assets	$ 315,772	$ 300,175
Weighted average interest rate of held to maturity investments	10.00%	10.00%
Accounts payable and other accrued liabilities:
Accrued salaries, wages and commissions	$ 14,885	$ 33,961
Accrued interest payable	43,601	35,373
Servicing principal and interest payable	7,932	6,249
Deferred tax liability	32,977	32,977
Repair and denial reserve	8,041	6,974
Payable to related parties	6,650	7,038
PPP liabilities	28,494	36,182
Accrued professional fees	4,769	5,354
Lease payable	9,795	8,205
Other liabilities	36,752	35,168
Total accounts payable and other accrued liabilities	$ 193,896	$ 207,481
Minimum
Other assets:
Maturity term of held to maturity investments	1 year	1 year
Maximum
Other assets:
Maturity term of held to maturity investments	5 years	5 years