Summary of Stock Option Activity (Details) (Stock Options, USD $)	12 Months Ended
	Dec. 31, 2013
Stock Options
Changes in shares granted for stock options for the year
Options outstanding, Beginning Balance	791,440
Options, Exercised	(281,560)
Options, forfeited or expired	(451,070)
Options outstanding, Ending Balance	58,810
Options, Exercisable	58,810
Weighted-Average Exercise Price
Options outstanding, Weighted Average Exercise Price, Beginning Balance	$ 16.95
Options, exercised, weighted average exercise price	$ 15.37
Options, forfeited or expired, weighted average exercise price	$ 18.14
Options outstanding, Weighted Average Exercise Price, Ending Balance	$ 15.47
Options exercisable, Weighted Average Exercise Price	$ 15.47