Segment Reporting (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Net fee revenues from external sources	$ 29,367us-gaap_FeesAndCommissions	$ 25,780us-gaap_FeesAndCommissions
Net interest and dividend revenue	49us-gaap_InvestmentIncomeNet	123us-gaap_InvestmentIncomeNet
Other revenue	192us-gaap_OtherSalesRevenueNet	46us-gaap_OtherSalesRevenueNet
Total revenues	29,608us-gaap_Revenues	25,949us-gaap_Revenues
Economic Earnings	9,416whg_EconomicEarningsLosses	9,169whg_EconomicEarningsLosses
Restricted stock expense	3,678us-gaap_ShareBasedCompensation	3,479us-gaap_ShareBasedCompensation
Intangible amortization	90us-gaap_AmortizationOfIntangibleAssets	90us-gaap_AmortizationOfIntangibleAssets
Deferred taxes on goodwill	38us-gaap_DeferredOtherTaxExpenseBenefit	38us-gaap_DeferredOtherTaxExpenseBenefit
Net income	5,610us-gaap_NetIncomeLoss	5,562us-gaap_NetIncomeLoss
Segment assets	126,858us-gaap_Assets	101,415us-gaap_Assets	139,874us-gaap_Assets
Segment goodwill	11,255us-gaap_Goodwill	11,255us-gaap_Goodwill	11,255us-gaap_Goodwill
Operating Segments \| Advisory
Segment Reporting Information [Line Items]
Net fee revenues from external sources	24,217	20,752
Net intersegment revenues	3,627	3,381
Net interest and dividend revenue	49	122
Other revenue	191	45
Total revenues	28,084	24,300
Economic Earnings	10,717	10,739
Segment assets	146,948	102,777
Segment goodwill	5,219	5,219
Operating Segments \| Trust
Segment Reporting Information [Line Items]
Net fee revenues from external sources	5,150	5,028
Net interest and dividend revenue		1
Other revenue	1	1
Total revenues	5,151	5,030
Economic Earnings	503	222
Segment assets	15,327	14,957
Segment goodwill	6,036	6,036
Westwood Holdings
Segment Reporting Information [Line Items]
Economic Earnings	(1,804)	(1,792)
Segment assets	10,914	11,253
Intersegment Eliminations
Segment Reporting Information [Line Items]
Net intersegment revenues	(3,627)	(3,381)
Total revenues	(3,627)	(3,381)
Segment assets	$ (46,331)	$ (27,572)

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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