Supplemental Guarantor Condensed Consolidated Financial Statements - Condensed Consolidating Statement of Cash Flows (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017	Sep. 30, 2016	Mar. 31, 2016
Cash flows from operations:
Cash provided by (used in) operating activities	$ (41,986,000)		$ (40,772,000)
Cash flows from investing activities
Purchase of furniture, equipment and leasehold improvements	(1,550,000)		(1,762,000)
Cash used in investing activities	(1,550,000)		(1,762,000)
Cash flows from financing activities
Cash dividends paid on Class A non-voting and Class B voting common stock	(1,480,000)		(1,476,000)
Cash dividends paid to noncontrolling interest	(816,000)	$ (816,000)	0
Payments for Repurchase of Common Stock	(4,357,000)		(3,634,000)
Payments for employee taxes withheld related to vested share-based awards	(2,203,000)		(1,341,000)
Redemption of senior secured notes	49,900,000		48,100,000
Cash provided by financing activities	41,044,000		41,649,000
Net decrease in cash and cash equivalents	(2,492,000)		(885,000)
Cash and cash equivalents, beginning of period	64,913,000		63,364,000
Cash and cash equivalents, end of period	62,421,000		62,479,000
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
Cash used in investing activities	0		0
Cash flows from financing activities
Cash dividends paid on Class A non-voting and Class B voting common stock	0		0
Cash dividends paid to noncontrolling interest	0
Payments for Repurchase of Common Stock	0		0
Payments for employee taxes withheld related to vested share-based awards	0		0
Redemption of senior secured notes	0		0
Cash provided by financing activities	0		0
Net decrease in cash and cash equivalents	0		0
Cash and cash equivalents, beginning of period	0		0
Cash and cash equivalents, end of period	0		0
Guarantor Subsidiaries
Cash flows from operations:
Cash provided by (used in) operating activities	4,100,000		(2,467,000)
Cash flows from investing activities
Purchase of furniture, equipment and leasehold improvements	0		0
Cash used in investing activities	0		0
Cash flows from financing activities
Cash dividends paid on Class A non-voting and Class B voting common stock	0		0
Cash dividends paid to noncontrolling interest	0
Payments for Repurchase of Common Stock	0		0
Payments for employee taxes withheld related to vested share-based awards	0		0
Redemption of senior secured notes	0		0
Cash provided by financing activities	0		0
Net decrease in cash and cash equivalents	4,100,000		(2,467,000)
Cash and cash equivalents, beginning of period	10,284,000		2,586,000
Cash and cash equivalents, end of period	14,384,000		119,000
Non-Guarantor Subsidiaries
Cash flows from operations:
Cash provided by (used in) operating activities	(54,803,000)		(44,045,000)
Cash flows from investing activities
Purchase of furniture, equipment and leasehold improvements	(1,550,000)		(1,762,000)
Cash used in investing activities	(1,550,000)		(1,762,000)
Cash flows from financing activities
Cash dividends paid on Class A non-voting and Class B voting common stock	0		0
Cash dividends paid to noncontrolling interest	(816,000)
Payments for Repurchase of Common Stock	0		0
Payments for employee taxes withheld related to vested share-based awards	0		0
Redemption of senior secured notes	49,900,000		48,100,000
Cash provided by financing activities	49,084,000		48,100,000
Net decrease in cash and cash equivalents	(7,269,000)		2,293,000
Cash and cash equivalents, beginning of period	54,400,000		59,871,000
Cash and cash equivalents, end of period	47,131,000		62,164,000
Parent
Cash flows from operations:
Cash provided by (used in) operating activities	8,717,000		5,740,000
Cash flows from investing activities
Purchase of furniture, equipment and leasehold improvements	0		0
Cash used in investing activities	0		0
Cash flows from financing activities
Cash dividends paid on Class A non-voting and Class B voting common stock	(1,480,000)		(1,476,000)
Cash dividends paid to noncontrolling interest	0
Payments for Repurchase of Common Stock	(4,357,000)		(3,634,000)
Payments for employee taxes withheld related to vested share-based awards	(2,203,000)		(1,341,000)
Redemption of senior secured notes	0		0
Cash provided by financing activities	(8,040,000)		(6,451,000)
Net decrease in cash and cash equivalents	677,000		(711,000)
Cash and cash equivalents, beginning of period	229,000		907,000
Cash and cash equivalents, end of period	$ 906,000		$ 196,000