CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities:
Net loss	$ (66,315,000)	$ (305,857,000)	$ (2,699,000)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:
Depreciation and amortization	14,890,000	18,509,000	30,799,000
Amortization of right-of-use assets under operating leases	10,245,000	11,769,000	0
Amortization of intangible assets	14,720,000	19,021,000	28,412,000
Unrealized (gain) loss on investment in equity securities	(4,004,000)	(14,431,000)	12,972,000
Goodwill and intangible assets write-off from business exits	0	5,900,000	2,640,000
Share-based compensation expense	7,804,000	11,874,000	10,192,000
Bad debt expense	2,229,000	720,000	2,830,000
Amortization of debt discount	666,000	666,000	717,000
Amortization of debt issuance costs	730,000	736,000	965,000
Deferred income taxes	5,033,000	307,339,000	(5,791,000)
Loss on disposal of fixed assets	461,000	750,000	727,000
Gain on sale of businesses	0	(17,814,000)	(13,688,000)
Loss on debt refinancing	0	0	4,434,000
Changes in operating assets and liabilities (excludes effect of sale of businesses):
Accounts receivable	14,973,000	(12,207,000)	14,556,000
Short-term investments in real estate	0	39,873,000	(10,468,000)
Prepaid expenses and other current assets	(4,140,000)	13,628,000	4,617,000
Other assets	947,000	(132,000)	2,278,000
Accounts payable and accrued expenses	(10,338,000)	(16,257,000)	1,651,000
Current and non-current operating lease liabilities	(10,599,000)	(12,738,000)
Other current and non-current liabilities	297,000	(4,661,000)	(16,742,000)
Net cash (used in) provided by operating activities	(22,401,000)	46,688,000	68,402,000
Cash flows from investing activities:
Additions to premises and equipment	(2,705,000)	(2,161,000)	(3,916,000)
Proceeds received from sale of equity securities	46,622,000	7,994,000	0
Proceeds from the sale of businesses	3,307,000	38,632,000	15,000,000
Other investing activities	0	422,000	0
Net cash provided by investing activities	47,224,000	44,887,000	11,084,000
Cash flows from financing activities:
Proceeds from issuance of long-term debt	0	0	407,880,000
Repayments and repurchases of long-term debt	(46,622,000)	(44,996,000)	(486,759,000)
Debt issuance costs	0	0	(5,042,000)
Proceeds from stock option exercises	0	400,000	3,644,000
Purchase of treasury shares	0	(19,995,000)	(40,362,000)
Distributions to non-controlling interests	(1,101,000)	(2,752,000)	(2,819,000)
Payments of tax withholding on issuance of restricted share units and restricted shares	(1,587,000)	(1,695,000)	(825,000)
Net cash used in financing activities	(49,310,000)	(69,038,000)	(124,283,000)
Net (decrease) increase in cash, cash equivalents and restricted cash	(24,487,000)	22,537,000	(44,797,000)
Cash, cash equivalents and restricted cash at the beginning of the period	86,583,000	64,046,000	108,843,000
Cash, cash equivalents and restricted cash at the end of the period	62,096,000	86,583,000	64,046,000
Supplemental cash flow information:
Interest paid	15,697,000	20,856,000	24,123,000
Income taxes paid, net	2,061,000	2,688,000	7,136,000
Acquisition of right-of-use assets with operating lease liabilities	1,075,000	13,775,000
Reduction of right-of-use assets from operating lease modifications or reassessments	(1,691,000)	(5,844,000)
Non-cash investing and financing activities:
Net increase (decrease) in payables for purchases of premises and equipment	$ 139,000	$ (101,000)	$ (32,000)