Business Acquisitions (Fair Value of Assets Acquired and Liabilities Assumed) (Details) - USD ($) $ in Thousands		3 Months Ended
	Jan. 01, 2019	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Business Acquisition [Line Items]
Goodwill		$ 119,641	$ 6,024	$ 6,024
Removal of preexisting ownership interest, including associated cumulative translation adjustment		(159,459)	$ 0
Pre-tax loss on derecognition of preexisting ownership interest		$ 3,516
LTG
Business Acquisition [Line Items]
Cash and cash equivalents	$ 21,923
Accounts receivable	320,467
Inventories	456,963
Commodity derivative assets - current	82,595
Other current assets	27,473
Commodity derivative assets - noncurrent	13,576
Goodwill	113,617
Other intangible assets	116,200
Right of use asset	42,972
Equity method investments	28,728
Other assets, net	2,211
Property, plant and equipment, net	173,388
Total Assets Acquired	1,400,113
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	63,263
Other long-term liabilities, including commodity derivative liabilities - noncurrent	3,174
Long-term debt, including current maturities	25,810
Long-term debt, including current maturities	161,688
Deferred income taxes	15,577
Total Liabilities Assumed	920,288
Fair value of acquired assets and assumed liabilities	479,825
Total purchase price consideration	$ 323,882