CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Preferred Stock, par value per share	$ 5.00	$ 5.00
Preferred Stock, shares authorized	2,000,000us-gaap_PreferredStockSharesAuthorized	2,000,000us-gaap_PreferredStockSharesAuthorized
Preferred Stock, shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Treasury stock, shares	8,459,498us-gaap_TreasuryStockShares	8,459,498us-gaap_TreasuryStockShares
Common Class A [Member]
Common Stock, par value per share	$ 0.001	$ 0.001
Common Stock, shares authorized	100,000,000	100,000,000
Common Stock, shares issued	37,175,813	37,085,489
Common Class B [Member]
Common Stock, par value per share	$ 0.001	$ 0.001
Common Stock, shares authorized	25,000,000	25,000,000
Common Stock, shares issued	3,235,048	3,235,048
Common Stock, shares outstanding	3,235,048	3,235,048

Face amount or stated value per share of common stock.

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