Restructuring Charges and Asset Impairments (Restructuring Charges) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Restructuring Costs
Balance Beginning	$ 15,449	$ 43,720
Expenses, net	9,086	12,407
Cash payments	(14,283)	(27,528)
Balance Ending	$ 10,252	28,599
Minimum
Restructuring Costs
Restructuring reserve, expected payment period	12 months
Maximum
Restructuring Costs
Restructuring reserve, expected payment period	24 months
Severance and benefits costs
Restructuring Costs
Balance Beginning	$ 13,641	42,151
Expenses, net	8,379	7,990
Cash payments	(12,064)	(26,942)
Balance Ending	9,956	23,199
Other exit costs
Restructuring Costs
Balance Beginning	1,808	1,569
Expenses, net	707	4,417
Cash payments	(2,219)	(586)
Balance Ending	$ 296	$ 5,400