CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Preferred Stock [Member] Convertible Preferred Stock [Member]	Common Stock [Member] Common Stock Class A	Common Stock [Member] Common Stock Class B	Common Stock [Member] Common Stock Class C	Common Stock [Member] Common Stock Class D	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Total
BALANCE at Dec. 31, 2020	$ 0	$ 4	$ 3	$ 3	$ 38	$ 991,769	$ (804,919)	$ 186,898
Consolidated net income	0	0	0	0	0	0	7	7
Stock-based compensation expense	0	0	0	0	0	253	0	253
Repurchase of shares of common stock	0	0	0	0	(1)	(871)	0	(872)
Issuance of shares of Class A common stock	0	2	0	0	0	12,123	0	12,125
Adjustment of redeemable noncontrolling interests to estimated redemption value	0	0	0	0	0	420	0	420
BALANCE at Mar. 31, 2021	0	6	3	3	37	1,003,694	(804,912)	198,831
BALANCE at Dec. 31, 2021	0	9	3	2	37	1,020,636	(766,567)	254,120
Consolidated net income	0	0	0	0	0	0	16,369	16,369
Stock-based compensation expense	0	0	0	0	0	124	0	124
Repurchase of shares of common stock						(10)		(10)
Adjustment of redeemable noncontrolling interests to estimated redemption value	0	0	0	0	0	(39)	0	(39)
BALANCE at Mar. 31, 2022	$ 0	$ 9	$ 3	$ 2	$ 37	$ 1,020,711	$ (750,198)	$ 270,564