Organizational Efficiency Plan and Executive Severance (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restructuring Cost and Reserve [Line Items]
Employee termination and other charges	$ 3,792	$ 1,489	$ 1,147
Severance costs	2,000
Accrued severance costs		$ 0	$ 0	$ 183
Employee Severance
Restructuring Cost and Reserve [Line Items]
Accrued severance costs	$ 1,100