Stock Compensation Plans - Option Plan By Exercise Price Range (Details) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Stock Option Plan, Exercise Price Range [Line Items]
Exercisable Options Weighted Average Exercise Price	$ 5.67
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Remaining Contractual Term	4 years 8 months 12 days
Range One [Member]
Stock Option Plan, Exercise Price Range [Line Items]
Range of exercise prices, lower range limit (in dollars per share)	$ 1.00
Exercisable Options Weighted Average Exercise Price	$ 1.90
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Remaining Contractual Term	7 years 10 months 24 days
Range Two [Member]
Stock Option Plan, Exercise Price Range [Line Items]
Range of exercise prices, lower range limit (in dollars per share)	$ 4.00
Exercisable Options Weighted Average Exercise Price	$ 4.50
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Remaining Contractual Term	1 year 9 months 18 days
Range Three [Member]
Stock Option Plan, Exercise Price Range [Line Items]
Range of exercise prices, lower range limit (in dollars per share)	$ 15.00
Exercisable Options Weighted Average Exercise Price	$ 20.08
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Remaining Contractual Term	7 months 6 days
Employee Stock Option Plan And Appreciation Right Plan [Member]
Stock Option Plan, Exercise Price Range [Line Items]
Options Exercisable Price Range		19,061	35,612
Director's Plan [Member] | Employee Stock Option
Stock Option Plan, Exercise Price Range [Line Items]
Options Exercisable Price Range		4,725	12,724
Long Term Incentive Plan [Member] | Employee Stock Option
Stock Option Plan, Exercise Price Range [Line Items]
Options outstanding and exercisable (in shares)	217,139
Options outstanding and exercisable, weighted average exercise price (in dollars per share)	$ 3.93
Options outstanding and exercisable, weighted average remaining term	6 years 3 months 18 days
Options Exercisable Price Range	117,806
Long Term Incentive Plan [Member] | Employee Stock Option | Range One [Member]
Stock Option Plan, Exercise Price Range [Line Items]
Range of exercise prices, upper range limit (in dollars per share)	$ 3.99
Options outstanding and exercisable (in shares)	159,000
Options outstanding and exercisable, weighted average exercise price (in dollars per share)	$ 1.86
Options outstanding and exercisable, weighted average remaining term	8 years 1 month 6 days
Options Exercisable Price Range	59,667
Long Term Incentive Plan [Member] | Employee Stock Option | Range Two [Member]
Stock Option Plan, Exercise Price Range [Line Items]
Range of exercise prices, upper range limit (in dollars per share)	$ 14.99
Options outstanding and exercisable (in shares)	39,300
Options outstanding and exercisable, weighted average exercise price (in dollars per share)	$ 4.50
Options outstanding and exercisable, weighted average remaining term	1 year 9 months 18 days
Options Exercisable Price Range	39,300
Long Term Incentive Plan [Member] | Employee Stock Option | Range Three [Member]
Stock Option Plan, Exercise Price Range [Line Items]
Range of exercise prices, upper range limit (in dollars per share)	$ 21.00
Options outstanding and exercisable (in shares)	18,839
Options outstanding and exercisable, weighted average exercise price (in dollars per share)	$ 20.08
Options outstanding and exercisable, weighted average remaining term	7 months 6 days
Options Exercisable Price Range	18,839
Long Term Incentive Plan [Member] | Unrestricted Portion [Member]
Stock Option Plan, Exercise Price Range [Line Items]
Options Exercisable Price Range	217,139	271,869	130,709