Condensed Consolidating Financial Information - Condensed Consolidating Statement of Cash Flows (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Cash provided by (used in) operating activities	$ (89,799)	$ 13,737
Cash flows from investing activities
Purchase of office facilities	(3,613)	(3,366)
Cash used in investing activities	(3,613)	(3,366)
Cash flows from financing activities
Cash dividends paid on Class A non-voting and Class B voting common stock	(4,531)	(4,483)
Issuance of Class A non-voting common stock	0	185
Repurchase of Class A non-voting common stock for cancellation	(6,618)	0
Tax benefit (deficiency) from share-based awards	(235)	1,275
Early Repayment of Senior Debt	0	(45,000)
Other financing activities	88,300	17,300
Cash flow provided by (used in) financing activities	76,916	(30,723)
Net increase (decrease) in cash and cash equivalents	(16,496)	(20,352)
Cash and cash equivalents, beginning of period	63,807	98,294
Cash and cash equivalents, end of period	47,311	77,942
Class A Stock [Member]
Cash flows from financing activities
Repurchase of Class A non-voting common stock for cancellation	(6,618)
Parent Company [Member]
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Cash provided by (used in) operating activities	11,548	48,737
Cash flows from investing activities
Purchase of office facilities	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	(4,531)	(4,483)
Issuance of Class A non-voting common stock		185
Tax benefit (deficiency) from share-based awards	(235)	1,275
Early Repayment of Senior Debt		(45,000)
Other financing activities	0	0
Cash flow provided by (used in) financing activities	(11,384)	(48,023)
Net increase (decrease) in cash and cash equivalents	164	714
Cash and cash equivalents, beginning of period	439	448
Cash and cash equivalents, end of period	603	1,162
Parent Company [Member] | Class A Stock [Member]
Cash flows from financing activities
Repurchase of Class A non-voting common stock for cancellation	(6,618)
Guarantor Subsidiaries [Member]
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Cash provided by (used in) operating activities	(180)	(25,778)
Cash flows from investing activities
Purchase of office facilities	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
Issuance of Class A non-voting common stock		0
Tax benefit (deficiency) from share-based awards	0	0
Early Repayment of Senior Debt		0
Other financing activities	0	0
Cash flow provided by (used in) financing activities	0	0
Net increase (decrease) in cash and cash equivalents	(180)	(25,778)
Cash and cash equivalents, beginning of period	1,557	30,901
Cash and cash equivalents, end of period	1,377	5,123
Guarantor Subsidiaries [Member] | Class A Stock [Member]
Cash flows from financing activities
Repurchase of Class A non-voting common stock for cancellation	0
Non-Guarantor Subsidiaries [Member]
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Cash provided by (used in) operating activities	(101,167)	(9,222)
Cash flows from investing activities
Purchase of office facilities	(3,613)	(3,366)
Cash used in investing activities	(3,613)	(3,366)
Cash flows from financing activities
Cash dividends paid on Class A non-voting and Class B voting common stock	0	0
Issuance of Class A non-voting common stock		0
Tax benefit (deficiency) from share-based awards	0	0
Early Repayment of Senior Debt		0
Other financing activities	88,300	17,300
Cash flow provided by (used in) financing activities	88,300	17,300
Net increase (decrease) in cash and cash equivalents	(16,480)	4,712
Cash and cash equivalents, beginning of period	61,811	66,945
Cash and cash equivalents, end of period	45,331	71,657
Non-Guarantor Subsidiaries [Member] | Class A Stock [Member]
Cash flows from financing activities
Repurchase of Class A non-voting common stock for cancellation	0
Consolidation, Eliminations [Member]
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Cash provided by (used in) operating activities	0	0
Cash flows from investing activities
Purchase of office facilities	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
Issuance of Class A non-voting common stock		0
Tax benefit (deficiency) from share-based awards	0	0
Early Repayment of Senior Debt		0
Other financing activities	0	0
Cash flow provided by (used in) financing activities	0	0
Net increase (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
Consolidation, Eliminations [Member] | Class A Stock [Member]
Cash flows from financing activities
Repurchase of Class A non-voting common stock for cancellation	$ 0