Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014 Segment		Sep. 30, 2013
Segment Reporting Information [Line Items]
Number of business segments					4
Net sales
Net sales	$ 654,975		$ 697,802		$ 1,306,560		$ 1,380,044
Operating income (loss)
Operating income (loss)	(2,973)		8,040		(18,508)		(8,091)
Restructuring and impairments, net	14,950	[1]	2,601	[1]	17,632	[1]	11,325	[1]
Total operating income (loss)	(17,923)		5,439		(36,140)		(19,416)
Depreciation and Amortization
Depreciation and amortization	18,979		19,436		39,463		39,927
Capital expenditures
Capital expenditures	22,376		16,736		45,968		36,268
Transportation Americas
Net sales
Net sales	159,902		185,233		318,656		375,445
Operating income (loss)
Operating income (loss)	(8,626)		(5,119)		(29,279)		(21,064)
Restructuring and impairments, net	13,654		1,941		13,862		9,280
Depreciation and Amortization
Depreciation and amortization	5,157		6,180		11,365		13,160
Capital expenditures
Capital expenditures	4,946		7,599		13,607		12,985
Transportation Europe & ROW
Net sales
Net sales	223,121		219,732		414,452		406,169
Operating income (loss)
Operating income (loss)	6,007		4,498		6,455		(29)
Restructuring and impairments, net	580		(2,207)		171		(2,284)
Depreciation and Amortization
Depreciation and amortization	5,684		4,978		11,643		10,201
Capital expenditures
Capital expenditures	10,638		5,239		19,685		15,996
Industrial Energy Americas
Net sales
Net sales	77,122		104,741		184,969		206,358
Operating income (loss)
Operating income (loss)	5,414		13,074		10,762		17,700
Restructuring and impairments, net	57		63		109		156
Depreciation and Amortization
Depreciation and amortization	2,615		2,884		5,229		5,863
Capital expenditures
Capital expenditures	2,386		406		3,704		1,392
Industrial Energy Europe & ROW
Net sales
Net sales	194,830		188,096		388,483		392,072
Operating income (loss)
Operating income (loss)	4,731		4,172		9,158		10,250
Restructuring and impairments, net	654		2,589		3,485		3,659
Depreciation and Amortization
Depreciation and amortization	4,203		4,186		8,552		8,531
Capital expenditures
Capital expenditures	3,162		2,014		6,252		3,598
Unallocated corporate expenses
Operating income (loss)
Operating income (loss)	(10,499)		(8,585)		(15,604)		(14,948)
Restructuring and impairments, net	5		215		5		514
Depreciation and Amortization
Depreciation and amortization	1,320		1,208		2,674		2,172
Capital expenditures
Capital expenditures	$ 1,244		$ 1,478		$ 2,720		$ 2,297

[1] See Note 13 to the Consolidated Financial Statements.