Consolidated Statements of Stockholders Equity (Parenthetical) (USD $)	Dec. 31, 2014
Common Class A [Member]
Common stock, par value
Common Class B [Member]
Common stock, par value
Common Stock [Member] | Common Class A [Member]
Common stock, par value	$ 1
Common Stock [Member] | Common Class B [Member]
Common stock, par value	$ 1