Business Acquisitions (Fair Value of Assets Acquired and Liabilities Assumed) (Details) - USD ($) $ in Thousands		3 Months Ended	6 Months Ended
	Jan. 01, 2019	Jun. 30, 2019	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Business Acquisition [Line Items]
Goodwill		$ 135,872	$ 135,872	$ 6,024	$ 6,024
Removal of preexisting ownership interest, including associated cumulative translation adjustment			(159,459)	$ 0
Pretax loss on derecognition of preexisting ownership interest		$ 2,400	$ 1,078
LTG
Business Acquisition [Line Items]
Cash and cash equivalents	$ 21,525
Accounts receivable	320,467
Inventories	456,963
Commodity derivative assets - current	82,595
Other current assets	27,474
Commodity derivative assets - noncurrent	13,576
Goodwill	129,848
Other intangible assets	106,600
Right of use asset	37,894
Equity method investments	28,728
Other assets, net	5,582
Property, plant and equipment, net	171,820
Total Assets Acquired	1,403,072
Short-term debt	218,901
Trade and other payables	303,321
Commodity derivative liabilities - current	29,024
Customer prepayments and deferred revenue	99,530
Accrued expense and other current liabilities	64,512
Other long-term liabilities, including commodity derivative liabilities - noncurrent	3,175
Long-term debt, including current maturities	21,193
Long-term debt, including current maturities	161,688
Deferred income taxes	14,403
Total Liabilities Assumed	915,747
Fair value of acquired assets and assumed liabilities	487,325
Total purchase price consideration	$ 328,944