Segment Information (Tables)

12 Months Ended

Mar. 31, 2018

Segment Reporting [Abstract]

Schedule of Segment Reporting Information by Segment

		Years Ended March 31,
	Analysis of Segment Assets	2018		2017		2016
Segment assets:
	North America	$	379,354	$	375,782	$	338,834
	Other Regions	1,587,277		1,596,090		1,629,364
	Total assets	$	1,966,631	$	1,971,872	$	1,968,198
Trade and other receivables, net:
	North America	$	46,096	$	40,212	$	48,229
	Other Regions	258,303		213,973		352,779
	Total trade and other receivables, net	$	304,399	$	254,185	$	401,008
Goodwill:
	North America	$	2,795	$	2,794	$	2,794
	Other Regions	24,751		13,669		13,669
	Total Goodwill	$	27,546	$	16,463	$	16,463
Equity in net assets of investee companies:
	North America	$	—	$	—	$	—
	Other Regions	67,369		51,443		57,243
	Total equity in net assets of investee companies	$	67,369	$	51,443	$	57,243
Depreciation and amortization:
	North America	$	7,454	$	7,543	$	6,432
	Other Regions	26,144		26,933		21,929
	Total depreciation and amortization	$	33,598	$	34,476	$	28,361
Capital expenditures:
	North America	$	4,407	$	3,638	$	7,516
	Other Regions	18,891		9,099		10,270
	Total capital expenditures	$	23,298	$	12,737	$	17,786

		Years Ended March 31,
	Analysis of Segment Operations	2018			2017			2016
Sales and other operating revenues:
	North America	$	451,383		$	396,217		$	468,098
	Other Regions	1,394,583			1,318,533			1,436,494
	Total revenue	$	1,845,966		$	1,714,750		$	1,904,592
Operating income:
	North America	$	22,394		$	15,333		$	25,230
	Other Regions	88,209			69,235			176,557
Total operating income		110,603			84,568			201,787
	Debt retirement expense (income)	(2,975		)	(300		)	—
	Interest expense	132,978			132,667			117,190
	Interest income	3,271			8,157			7,077
Income (loss) before income taxes and other items		$	(16,129	)	$	(39,642	)	$	91,674

Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area

		Years Ended March 31,
	Sales by Destination	2018		2017		2016
Sales and Other Operating Revenues:
	United States	$	291,804	$	272,161	$	311,634
	China	249,549		230,226		209,781
	Belgium	137,313		115,632		132,817
	Northern Africa	111,971		32,839		59,523
	Other	1,055,329		1,063,892		1,190,837
	Total	$	1,845,966	$	1,714,750	$	1,904,592

Schedule of Long-Lived Assets in Individual Foreign Countries

		Years Ended March 31,
Property, Plant and Equipment by Location		2018		2017		2016
Property, Plant and Equipment, Net:
	Brazil	$	72,190	$	77,653	$	82,307
	United States	54,233		56,028		59,713
	Zimbabwe	51,768		48,738		51,295
	Malawi	21,571		22,299		24,609
	Tanzania	18,884		20,997		22,831
	Argentina	6,252		6,580		6,914
	Asia	6,199		6,130		6,447
	Europe	5,781		5,467		6,895
	Zambia	1,067		3,877		4,366
	Turkey	2,282		2,654		2,955
	Other	14,054		6,088		9,193
	Total	$	254,281	$	256,511	$	277,525