Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Preferred stock, par value	$ 0.50	$ 0.50
Preferred stock, shares authorized	10,000,000us-gaap_PreferredStockSharesAuthorized	10,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Common Stock
Common stock, par value	$ 0.50	$ 0.50
Common stock, shares authorized	60,000,000	60,000,000
Common stock, shares outstanding	36,444,289	36,364,297
Treasury stock, shares	6,322,650	6,322,650
Class B Common Stock
Common stock, par value	$ 0.50	$ 0.50
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares outstanding	4,933,245	4,733,737
Treasury stock, shares	48,263	48,263

Face amount or stated value per share of common stock.

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