Consolidated Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Cash flows from operating activities:
Net income (loss)	$ (16,279,000)	$ 1,424,000	$ 4,840,000	$ (1,808,000)	$ (14,855,000)	$ 3,033,000
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	4,306,000		4,019,000		8,222,000	7,958,000
Impairment charge	22,368,000				22,368,000		$ 0
Deferred income taxes					1,472,000	1,029,000
Non-cash interest					489,000	538,000
Amortization of syndication contracts					249,000	352,000
Payments on syndication contracts					(227,000)	(360,000)
Equity in net (income) loss of nonconsolidated affiliate					158,000	98,000
Non-cash stock-based compensation					1,635,000	2,425,000
(Gain) loss on disposal of property and equipment					161,000
Changes in assets and liabilities:
(Increase) decrease in accounts receivable					9,619,000	9,170,000
(Increase) decrease in prepaid expenses and other assets					2,680,000	(6,547,000)
Increase (decrease) in accounts payable, accrued expenses and other liabilities					(12,301,000)	(780,000)
Net cash provided by operating activities					19,670,000	16,916,000
Cash flows from investing activities:
Proceeds from sale of property and equipment and intangibles						33,000
Purchases of property and equipment					(13,982,000)	(5,710,000)
Purchases of intangible assets						(3,153,000)
Purchase of a businesses, net of cash acquired						(3,563,000)
Purchases of marketable securities					(1,160,000)	(159,403,000)
Proceeds from marketable securities					21,681,000	25,000,000
Purchases of investments					(300,000)	(35,000)
Net cash provided by (used in) investing activities					6,239,000	(146,831,000)
Cash flows from financing activities:
Proceeds from stock option exercises						106,000
Tax payments related to shares withheld for share-based compensation plans					(751,000)	(2,239,000)
Payments on long-term debt					(1,500,000)	(1,500,000)
Dividends paid					(8,540,000)	(8,960,000)
Repurchase of Class A common stock					(9,008,000)	(7,660,000)
Payment of contingent consideration						(2,015,000)
Payments of capitalized debt costs					(225,000)
Net cash used in financing activities					(20,024,000)	(22,268,000)
Effect of exchange rates on cash, cash equivalents and restricted cash					13,000	(10,000)
Net increase (decrease) in cash, cash equivalents and restricted cash					5,898,000	(152,193,000)
Cash, cash equivalents and restricted cash:
Beginning		$ 47,465,000		$ 261,854,000	47,465,000	261,854,000	261,854,000
Ending	$ 53,363,000		$ 109,661,000		53,363,000	109,661,000	$ 47,465,000
Cash payments for:
Interest					6,555,000	6,861,000
Income taxes					1,873,000	692,000
Supplemental disclosures of non-cash investing and financing activities:
Capital expenditures financed through accounts payable, accrued expenses and other liabilities					1,530,000	400,000
Contingent consideration included in accounts payable, accrued expenses and other liabilities					$ 5,743,000	$ 11,280,000