Shareholders' Equity (Details) - Restricted Stock Units (RSUs) [Member] shares in Thousands, $ in Thousands	6 Months Ended
	Jun. 30, 2019 USD ($) Age shares	Jun. 30, 2018 USD ($) shares
Restricted stock units under the long-term Incentive Plans [Abstract]
Vesting period	5 years
Retirement age | Age	65
Awards granted in February 2017 and after	3 years
Restricted stock units vested (in shares) | shares	22	32
Shares withheld upon vesting (in shares) | shares	4	8
Vesting date fair value of vested restricted stock units during the period	$ 777	$ 1,853
Grant date fair value of restricted stock units granted	2,098	3,553
Compensation expense	$ 1,380	$ 1,019
Non-Employee Directors Compensation Plan [Member]
Restricted stock units under the long-term Incentive Plans [Abstract]
Vesting period	1 year