Stockholders' Equity Preferred Stock Purchase Rights (Details) (Series A Junior Participating Preferred Stock [Member], USD $)	12 Months Ended
	Dec. 31, 2013
Series A Junior Participating Preferred Stock [Member]
Class of Warrant or Right [Line Items]
Number of rights attached to each share of common stock	1
Number of days following public announcement that the rights to become exercisable (in number of days	10 days
Beneficial ownership by a person or group of affiliated persons before rights become exercisable (as a percent)	20.00%
Number of days following the commencement of a tender offer or exchange offer that the rights to become exercisable (in number of days)	10 days
Fraction of newly issued share of Series A Junior Participating Preferred Stock that could be purchased for each Right	0.01
Series A Junior Participating Preferred Stock, Purchase Price	$ 125