Restructuring (Summary of Restructuring Accrual) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
Restructuring Reserve [Roll Forward]
Balance at January 1, 2019	$ 0
Charges	1,780
Cash payments	(1,592)
Balance at December 31, 2019	188
Severance and Employee Benefit Costs
Restructuring Reserve [Roll Forward]
Balance at January 1, 2019	0
Charges	1,466
Cash payments	(1,317)
Balance at December 31, 2019	149
Contract Cancellations
Restructuring Reserve [Roll Forward]
Balance at January 1, 2019	0
Charges	314
Cash payments	(275)
Balance at December 31, 2019	$ 39