Supplemental Guarantor Condensed Consolidated Financial Statements - Condensed Consolidating Statement of Cash Flows (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operations:
Cash provided by (used in) continuing operations	$ 78,315	$ (3,429)	$ (9,452)
Cash flows from investing activities
Purchase of office facilities	(4,398)	(14,012)	(14,739)
Cash used in investing activities	(4,398)	(14,012)	(14,739)
Cash flows from financing activities
Cash dividends paid on Class A non-voting and Class B voting common stock	(5,983)us-gaap_PaymentsOfDividendsCommonStock	(5,978)us-gaap_PaymentsOfDividendsCommonStock	(5,986)us-gaap_PaymentsOfDividendsCommonStock
Issuance of Class A non-voting common stock	185	150	0
Repurchase of Class A non-voting common stock for cancellation	0	(3,625)	(1,866)
Tax benefit (deficiency) from share-based awards	1,194	(78)	(720)
Redemption of senior secured notes	(45,000)us-gaap_EarlyRepaymentOfSeniorDebt	0us-gaap_EarlyRepaymentOfSeniorDebt	0us-gaap_EarlyRepaymentOfSeniorDebt
Acquisition of non-controlling interest	0	0	(3,000)
Decrease in bank call loans, net	(58,800)	(10,100)	100,800
Cash (used in) provided by financing activities	(108,404)	(19,631)	89,228
Net (decrease) increase in cash and cash equivalents	(34,487)	(37,072)	65,037
Cash and cash equivalents, beginning of year	98,294	135,366	70,329
Cash and cash equivalents, end of year	63,807	98,294	135,366
Eliminations
Cash flows from operations:
Cash provided by (used in) continuing operations	0	0	0
Cash flows from investing activities
Purchase of office facilities	0	0	0
Cash used in 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
Issuance of Class A non-voting common stock	0	0
Repurchase of Class A non-voting common stock for cancellation		0	0
Tax benefit (deficiency) from share-based awards	0	0	0
Redemption of senior secured notes	0
Acquisition of non-controlling interest			0
Decrease in bank call loans, net	0	0	0
Cash (used in) provided by financing activities	0	0	0
Net (decrease) increase 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) continuing operations	(29,344)	(9,757)	31,776
Cash flows from investing activities
Purchase of office facilities	0	0	0
Cash used in 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
Issuance of Class A non-voting common stock	0	0
Repurchase of Class A non-voting common stock for cancellation		0	0
Tax benefit (deficiency) from share-based awards	0	0	0
Redemption of senior secured notes	0
Acquisition of non-controlling interest			(3,000)
Decrease in bank call loans, net	0	0	0
Cash (used in) provided by financing activities	0	0	(3,000)
Net (decrease) increase in cash and cash equivalents	(29,344)	(9,757)	28,776
Cash and cash equivalents, beginning of year	30,901	40,658	11,882
Cash and cash equivalents, end of year	1,557	30,901	40,658
Non-Guarantor Subsidiaries
Cash flows from operations:
Cash provided by (used in) continuing operations	58,064	(3,616)	(47,280)
Cash flows from investing activities
Purchase of office facilities	(4,398)	(14,012)	(14,739)
Cash used in investing activities	(4,398)	(14,012)	(14,739)
Cash flows from financing activities
Cash dividends paid on Class A non-voting and Class B voting common stock	0	0	0
Issuance of Class A non-voting common stock	0	0
Repurchase of Class A non-voting common stock for cancellation		0	0
Tax benefit (deficiency) from share-based awards	0	0	0
Redemption of senior secured notes	0
Acquisition of non-controlling interest			0
Decrease in bank call loans, net	(58,800)	(10,100)	100,800
Cash (used in) provided by financing activities	(58,800)	(10,100)	100,800
Net (decrease) increase in cash and cash equivalents	(5,134)	(27,728)	38,781
Cash and cash equivalents, beginning of year	66,945	94,673	55,892
Cash and cash equivalents, end of year	61,811	66,945	94,673
Parent
Cash flows from operations:
Cash provided by (used in) continuing operations	49,595	9,944	6,052
Cash flows from investing activities
Purchase of office facilities	0	0	0
Cash used in investing activities	0	0	0
Cash flows from financing activities
Cash dividends paid on Class A non-voting and Class B voting common stock	(5,983)	(5,978)	(5,986)
Issuance of Class A non-voting common stock	185	150
Repurchase of Class A non-voting common stock for cancellation		(3,625)	(1,866)
Tax benefit (deficiency) from share-based awards	1,194	(78)	(720)
Redemption of senior secured notes	(45,000)
Acquisition of non-controlling interest			0
Decrease in bank call loans, net		0	0
Cash (used in) provided by financing activities	(49,604)	(9,531)	(8,572)
Net (decrease) increase in cash and cash equivalents	(9)	413	(2,520)
Cash and cash equivalents, beginning of year	448	35	2,555
Cash and cash equivalents, end of year	$ 439	$ 448	$ 35

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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