Condensed Consolidating Financial Information - Condensed Consolidating Statement of Cash Flows (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Cash used in operating activities	$ (126,388)	$ (13,390)
Cash flows from investing activities
Purchase of office facilities	(1,913)	(2,185)
Cash used in investing activities	(1,913)	(2,185)
Cash flows from investing activities
Cash dividends paid on Class A non-voting and Class B voting common stock	(3,023)	(2,984)
Issuance of Class A non-voting common stock	0	185
Tax benefit (deficiency) from share-based awards	(270)	1,254
Early Repayment of Senior Debt	0	(45,000)
Other financing activities	118,100	29,000
Cash flow provided by (used in) financing activities	114,807	(17,545)
Net increase (decrease) in cash and cash equivalents	(13,494)	(33,120)
Cash and cash equivalents, beginning of period	63,807	98,294
Cash and cash equivalents, end of period	50,313	65,174
Parent Company [Member]
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Cash used in operating activities	2,883	47,295
Cash flows from investing activities
Purchase of office facilities	0	0
Cash used in investing activities	0	0
Cash flows from investing activities
Cash dividends paid on Class A non-voting and Class B voting common stock	(3,023)	(2,984)
Issuance of Class A non-voting common stock		185
Tax benefit (deficiency) from share-based awards	(270)	1,254
Early Repayment of Senior Debt		(45,000)
Other financing activities	0	0
Cash flow provided by (used in) financing activities	(3,293)	(46,545)
Net increase (decrease) in cash and cash equivalents	(410)	750
Cash and cash equivalents, beginning of period	439	448
Cash and cash equivalents, end of period	29	1,198
Guarantor Subsidiaries [Member]
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Cash used in operating activities	1,128	(24,341)
Cash flows from investing activities
Purchase of office facilities	0	0
Cash used in investing activities	0	0
Cash flows from investing 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	1,128	(24,341)
Cash and cash equivalents, beginning of period	1,557	30,901
Cash and cash equivalents, end of period	2,685	6,560
Non-Guarantor Subsidiaries [Member]
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Cash used in operating activities	(130,399)	(36,344)
Cash flows from investing activities
Purchase of office facilities	(1,913)	(2,185)
Cash used in investing activities	(1,913)	(2,185)
Cash flows from investing 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	118,100	29,000
Cash flow provided by (used in) financing activities	118,100	29,000
Net increase (decrease) in cash and cash equivalents	(14,212)	(9,529)
Cash and cash equivalents, beginning of period	61,811	66,945
Cash and cash equivalents, end of period	47,599	57,416
Consolidation, Eliminations [Member]
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Cash 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 investing 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