Supplemental Guarantor Condensed Consolidated Financial Statements - Condensed Consolidating Statement of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operations:
Cash provided by (used in) operating activities	$ 168,570	$ (16,136)	$ (66,865)
Cash flows from investing activities
Purchase of furniture, equipment and leasehold improvements	(8,672)	(5,611)	(5,731)
Proceeds from Sale of Other Assets, Investing Activities			45,448
Payments to Acquire Intangible Assets	(400)	0	0
Proceeds from Life Insurance Policy	881	1,744	0
Cash (used in) provided by investing activities	(8,191)	(3,867)	39,717
Cash flows from financing activities
Cash dividends paid on Class A non-voting and Class B voting common stock	(5,833)	(5,836)	(5,887)
Payments of Ordinary Dividends, Noncontrolling Interest	(372)	(2,448)	(5,740)
Issuance of Class A non-voting common stock	70	26	0
Payments for Repurchase of Common Stock	(5,894)	(7,464)	(3,935)
Payments Related to Tax Withholding for Share-based Compensation	(2,529)	(2,237)	(1,341)
Proceeds from Issuance of Long-term Debt		200,000
Repayments of Long-term Debt		(150,000)
Payments of Debt Issuance Costs	0	(1,297)	0
Redemption of senior secured notes	0	(150,000)	0
Redemption of senior secured notes	(103,300)	(27,500)	45,600
Cash (used in) provided by financing activities	(117,858)	3,244	28,697
Net increase (decrease) in cash and cash equivalents	42,521	(16,759)	1,549
Cash and cash equivalents, beginning of year	48,154	64,913	63,364
Cash and cash equivalents, end of year	90,675	48,154	64,913
Eliminations
Cash flows from operations:
Cash provided by (used in) operating activities		0	0
Cash flows from investing activities
Purchase of furniture, equipment and leasehold improvements	0	0	0
Proceeds from Sale of Other Assets, Investing Activities			0
Payments to Acquire Intangible Assets	0
Proceeds from Life Insurance Policy		0
Cash (used in) provided by investing activities	0	0	0
Cash flows from financing activities
Cash dividends paid on Class A non-voting and Class B voting common stock	0	0	0
Payments of Ordinary Dividends, Noncontrolling Interest	0	0	0
Issuance of Class A non-voting common stock	0	0
Payments for Repurchase of Common Stock	0	0	0
Payments Related to Tax Withholding for Share-based Compensation	0	0	0
Proceeds from Issuance of Long-term Debt		0
Repayments of Long-term Debt		0
Payments of Debt Issuance Costs		0
Redemption of senior secured notes	0	0	0
Cash (used in) provided by financing activities	0	0	0
Net increase (decrease) in cash and cash equivalents	0	0	0
Cash and cash equivalents, beginning of year	0	0	0
Cash and cash equivalents, end of year	0	0	0
Guarantor Subsidiaries
Cash flows from operations:
Cash provided by (used in) operating activities	510	(6,568)	7,698
Cash flows from investing activities
Purchase of furniture, equipment and leasehold improvements	0	0	0
Proceeds from Sale of Other Assets, Investing Activities			0
Payments to Acquire Intangible Assets	(400)
Proceeds from Life Insurance Policy		0
Cash (used in) provided by investing activities	(400)	0	0
Cash flows from financing activities
Cash dividends paid on Class A non-voting and Class B voting common stock	0	0	0
Payments of Ordinary Dividends, Noncontrolling Interest	0	0	0
Issuance of Class A non-voting common stock	0	0
Payments for Repurchase of Common Stock	0	0	0
Payments Related to Tax Withholding for Share-based Compensation	0	0	0
Proceeds from Issuance of Long-term Debt		0
Repayments of Long-term Debt		0
Payments of Debt Issuance Costs		0
Redemption of senior secured notes	0	0	0
Cash (used in) provided by financing activities	0	0	0
Net increase (decrease) in cash and cash equivalents	110	(6,568)	7,698
Cash and cash equivalents, beginning of year	3,716	10,284	2,586
Cash and cash equivalents, end of year	3,826	3,716	10,284
Non-Guarantor Subsidiaries
Cash flows from operations:
Cash provided by (used in) operating activities	107,790	16,411	(85,048)
Cash flows from investing activities
Purchase of furniture, equipment and leasehold improvements	(8,672)	(5,611)	(5,731)
Proceeds from Sale of Other Assets, Investing Activities			45,448
Payments to Acquire Intangible Assets	0
Proceeds from Life Insurance Policy	881	1,744
Cash (used in) provided by investing activities	(7,791)	(3,867)	39,717
Cash flows from financing activities
Cash dividends paid on Class A non-voting and Class B voting common stock	0	0	0
Payments of Ordinary Dividends, Noncontrolling Interest	(372)	(2,448)	(5,740)
Issuance of Class A non-voting common stock	0	0
Payments for Repurchase of Common Stock	0	0	0
Payments Related to Tax Withholding for Share-based Compensation	0	0	0
Proceeds from Issuance of Long-term Debt		0
Repayments of Long-term Debt		0
Payments of Debt Issuance Costs		0
Redemption of senior secured notes	(103,300)	(27,500)	45,600
Cash (used in) provided by financing activities	(103,672)	(29,948)	39,860
Net increase (decrease) in cash and cash equivalents	(3,673)	(17,404)	(5,471)
Cash and cash equivalents, beginning of year	36,996	54,400	59,871
Cash and cash equivalents, end of year	33,323	36,996	54,400
Parent Company [Member]
Cash flows from investing activities
Payments to Acquire Intangible Assets	0
Proceeds from Life Insurance Policy		0
Cash flows from financing activities
Payments of Ordinary Dividends, Noncontrolling Interest		0	0
Proceeds from Issuance of Long-term Debt	200,000
Parent
Cash flows from operations:
Cash provided by (used in) operating activities	60,270	(25,979)	10,485
Cash flows from investing activities
Purchase of furniture, equipment and leasehold improvements	0	0	0
Proceeds from Sale of Other Assets, Investing Activities			0
Cash (used in) provided by investing activities	0	0	0
Cash flows from financing activities
Cash dividends paid on Class A non-voting and Class B voting common stock	(5,833)	(5,836)	(5,887)
Payments of Ordinary Dividends, Noncontrolling Interest	0
Issuance of Class A non-voting common stock	70	26
Payments for Repurchase of Common Stock	(5,894)	(7,464)	(3,935)
Payments Related to Tax Withholding for Share-based Compensation	(2,529)	(2,237)	(1,341)
Repayments of Long-term Debt	(150,000)
Payments of Debt Issuance Costs	(1,297)
Redemption of senior secured notes	0	0	0
Cash (used in) provided by financing activities	(14,186)	33,192	(11,163)
Net increase (decrease) in cash and cash equivalents	46,084	7,213	(678)
Cash and cash equivalents, beginning of year	7,442	229	907
Cash and cash equivalents, end of year	$ 53,526	$ 7,442	$ 229