Comprehensive Income (Loss) and Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Changes in accumulated other comprehensive income (loss)
Balance at the beginning of the period			$ 112,481
Balance at the end of the period	$ 82,880		82,880
Net Accumulated Other Comprehensive Income (Loss)
Changes in accumulated other comprehensive income (loss)
Balance at the beginning of the period	(43,939)	$ (26,683)	(31,425)	$ (28,796)
Other comprehensive income (loss) before reclassifications	(2,849)	(9,882)	(17,237)	(8,400)
Amounts reclassified out of AOCI	1,261	1,178	3,135	1,809
Other comprehensive income (loss)	(1,588)	(8,704)	(14,102)	(6,591)
Balance at the end of the period	(45,527)	(35,387)	(45,527)	(35,387)
Foreign Currency Translation
Changes in accumulated other comprehensive income (loss)
Balance at the beginning of the period	(16,658)	(6,267)	(10,272)	(12,132)
Other comprehensive income (loss) before reclassifications	(689)	(4,466)	(7,075)	1,399
Other comprehensive income (loss)	(689)	(4,466)	(7,075)	1,399
Balance at the end of the period	(17,347)	(10,733)	(17,347)	(10,733)
Post-Retirement Benefit Plan Adjustments
Changes in accumulated other comprehensive income (loss)
Balance at the beginning of the period	1,072	1,119	1,114	1,159
Amounts reclassified out of AOCI	(43)	(39)	(85)	(79)
Other comprehensive income (loss)	(43)	(39)	(85)	(79)
Balance at the end of the period	1,029	1,080	1,029	1,080
Defined Benefit Pension Plans, Net of Tax
Changes in accumulated other comprehensive income (loss)
Balance at the beginning of the period	(14,998)	(20,196)	(15,161)	(20,363)
Amounts reclassified out of AOCI	164	245	327	412
Other comprehensive income (loss)	164	245	327	412
Balance at the end of the period	(14,834)	(19,951)	(14,834)	(19,951)
Accumulated tax expense (benefit)			2,000	2,200
Ownership Share of Equity Method Investees’ Other Comprehensive Income (Loss)
Changes in accumulated other comprehensive income (loss)
Balance at the beginning of the period	(12,123)	605	(6,739)	1,537
Other comprehensive income (loss) before reclassifications	(179)	(3,674)	(5,563)	(4,606)
Other comprehensive income (loss)	(179)	(3,674)	(5,563)	(4,606)
Balance at the end of the period	(12,302)	(3,069)	(12,302)	(3,069)
Foreign Exchange Contracts
Changes in accumulated other comprehensive income (loss)
Balance at the beginning of the period	(1,232)	(1,944)	(367)	1,003
Other comprehensive income (loss) before reclassifications	(1,981)	(1,742)	(4,599)	(5,193)
Amounts reclassified out of AOCI	1,140	972	2,893	1,476
Other comprehensive income (loss)	(841)	(770)	(1,706)	(3,717)
Balance at the end of the period	$ (2,073)	$ (2,714)	$ (2,073)	$ (2,714)