Accumulated Other Comprehensive Income (Loss) Schedule of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	$ 134,791	$ 97,612	$ 134,791	$ 97,612	$ 116,061	$ 70,476	$ 154,270	$ 267,175
Pretax income (loss)	(14,507)	48,367	(48,338)	132,797
Income tax effect	(699)	(1,532)	3,544	(12,269)
Reclassification of unrealized loss (gain)	(7,263)	12,391	(26,020)	44,630
Reclassification of deferred income taxes	(1,698)	4,598	(6,082)	16,573
Other comprehensive income from unconsolidated subsidiaries	643	(1,034)	2,160	(1,635)
Disposal of business, net				(1,925)
Adoption of ASU 2018-02 (see Note 4)			5,345
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	146,704	97,735	146,704	97,735	125,753	71,933	157,353	272,529
Pretax income (loss)	(23,405)	63,769	(82,137)	177,434
Income tax effect	(2,454)	4,151	(4,507)	4,151
Reclassification of unrealized loss (gain)	0
Reclassification of deferred income taxes	0
Other comprehensive income from unconsolidated subsidiaries	0
Disposal of business, net				1,511
Adoption of ASU 2018-02 (see Note 4)			2,859
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	(19,988)	(8,548)	(19,988)	(8,548)	(19,684)	(11,538)	(10,324)	(8,091)
Pretax income (loss)	7,681	(15,402)	33,901	(44,749)
Income tax effect	1,796	(5,683)	7,926	(16,463)
Reclassification of unrealized loss (gain)	(7,284)	12,591	(26,117)	45,551
Reclassification of deferred income taxes	(1,703)	4,648	(6,106)	16,808
Other comprehensive income from unconsolidated subsidiaries	0
Adoption of ASU 2018-02 (see Note 4)			2,486
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss		6,790		6,790
Reclassification of unrealized loss (gain)		(200)
Reclassification of deferred income taxes		50
Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	8,926	6,790	8,926	6,790	(10,200)	(8,772)	(6,640)	$ (2,737)
Pretax income (loss)	1,217		(102)	112
Income tax effect	(41)		125	43
Reclassification of unrealized loss (gain)	21		97	(921)
Reclassification of deferred income taxes	5		24	(235)
Other comprehensive income from unconsolidated subsidiaries	0
Disposal of business, net				(3,436)
Accumulated Gain (Loss) from Unconsoldated Subsidiaries [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	(851)	1,635	(851)	1,635	$ (208)	$ 1,309	$ 601
Pretax income (loss)	0
Income tax effect	0
Reclassification of unrealized loss (gain)	0
Reclassification of deferred income taxes	0
Other comprehensive income from unconsolidated subsidiaries	643	(1,034)	2,160	(1,635)
Cross Currency Fx Forward Contract [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	$ 2,000	$ 2,000	$ 6,000	$ 6,000