INVESTMENTS - Amortized Cost and Fair Value of TCA's Investment (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Available-for-Sale, Amortized Cost
Due in 1 year or less	$ 12,500,000
Due in 1-5 years	44,500,000
Due in 5-10 years	0
Due after 10 years	0
Total by maturity	57,000,000.0
Available-for-Sale, Fair Value
Due in 1 year or less	12,500,000
Due in 1-5 years	42,900,000
Due in 5-10 years	0
Due after 10 years	0
Total by maturity	55,400,000
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	129,800,000	$ 134,300,000
Fair Value	127,900,000	134,500,000
Debt securities, available-for-sale, realized gain	0
Debt securities, available-for-sale, realized loss	300,000
Equity securities, available-for-sale, realized gain	400,000
Equity securities, available-for-sale, realized loss	(400,000)
Mortgage and other asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	6,600,000	8,800,000
Fair Value	6,300,000	8,800,000
Common Stock
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	61,700,000	65,200,000
Fair Value	61,700,000	65,200,000
Other investments measured at net asset value
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,500,000	4,400,000
Fair Value	$ 4,500,000	$ 4,400,000