Consolidated Statements of Equity (Parenthetical) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Number of shares of common stock issued under stock option plan	67,029	227,410	582,730
Number of common stock shares purchased	154,633	60,595	251,312
Preferred stock		$ 1.375	$ 1.375
Common stock	$ 0.69	$ 0.65	$ 0.58
Common Stock Split Ratio Declared			2
Common Stock [Member]
Number of shares of common stock issued under stock option plan	67,029	227,410	582,730
Additional Paid-in Capital [Member]
Number of shares of common stock issued under stock option plan	67,029	227,410	582,730
Treasury Stock [Member]
Number of common stock shares purchased	154,633	60,595	251,312