Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	2,000,000us-gaap_PreferredStockSharesAuthorized	2,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Class A Common Stock [Member]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	40,000,000	40,000,000
Common stock, shares issued	22,509,452	22,389,369
Common stock, shares outstanding	21,567,744	21,447,661
Class B Common Stock [Member]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares issued	5,649,240	5,649,240
Common stock, shares outstanding	5,576,775	5,576,775

Face amount or stated value per share of common stock.

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