Shareholders' Equity and Stock Incentive Plans (Summary of SARs Activity) (Details) - Stock Appreciation Rights (SARs) [Member] - $ / shares	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
SARs, Outstanding, Beginning of period	1,330,924	714,238
SARs, Granted	770,775	616,686
SARs, Exercised	0	0
SARs, Forfeitures	0	0
SARs, Expirations	0	0
SARs, Outstanding, End of period	2,101,699	1,330,924
SARs, Vested, End of Period	919,800	543,018
SARs, Exercisable, End of Period	0	543,018
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Weighted Average Exercise Price [Roll Forward]
Weighted Average Exercise Prices, Outstanding, Beginning of Period	$ 21.35	$ 27.12
Weighted Average Exercise Prices, Granted	10.98	14.67
Weighted Average Exercise Prices, Exercised	0	0
Weighted Average Exercise Prices, Forfeitures	0	0
Weighted Average Exercise Prices, Expired	0	0
Weighted Average Exercise Prices, Outstanding, End of Period	17.55	21.35
Weighted Average Exercise Prices, Vested, End of Period	24.34	27.18
Weighted Average Exercise Prices, Exercisable, End of Period	$ 24.34	$ 27.18
Weighted Average Remaining Life, Outstanding, End of Period	4 years 10 months 24 days	4 years 9 months 18 days
Weighted Average Remaining Life, Exercisable, End of Period	3 years	3 years