Comprehensive Income (Loss) and Accumulated Other Comprehensive Income (Details) - USD ($)	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Changes in accumulated other comprehensive income (loss)
Balance at the beginning of the period	$ (26,683,000)	$ 17,583,000	$ (28,796,000)	$ 18,184,000
Other comprehensive income (loss) before reclassifications	(9,882,000)	(10,677,000)	(8,400,000)	(11,286,000)
Amounts reclassified out of AOCI	1,178,000	29,000	1,809,000	37,000
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(8,704,000)	(10,648,000)	(6,591,000)	(11,249,000)
Balance at the end of the period	(35,387,000)	6,935,000	(35,387,000)	6,935,000
Foreign Currency Translation
Changes in accumulated other comprehensive income (loss)
Balance at the beginning of the period	(6,267,000)	22,235,000	(12,132,000)	23,335,000
Other comprehensive income (loss) before reclassifications	(4,466,000)	(13,659,000)	1,399,000	(14,759,000)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(4,466,000)	(13,659,000)	1,399,000	(14,759,000)
Balance at the end of the period	(10,733,000)	8,576,000	(10,733,000)	8,576,000
Deferred Income Taxes Related to Other Comprehensive Income			0
Accumulated Defined Benefit Plans Adjustment [Member]
Changes in accumulated other comprehensive income (loss)
Balance at the beginning of the period	(20,196,000)	(7,326,000)	(20,363,000)	(7,386,000)
Amounts reclassified out of AOCI	245,000	81,000	412,000	141,000
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	245,000	81,000	412,000	141,000
Balance at the end of the period	(19,951,000)	(7,245,000)	(19,951,000)	(7,245,000)
Accumulated tax expense (benefit)	(2,200,000)	(2,200,000)	(2,200,000)	(2,200,000)
Post-Retirement Benefit Plans
Changes in accumulated other comprehensive income (loss)
Balance at the beginning of the period	1,119,000	1,412,000	1,159,000	1,464,000
Amounts reclassified out of AOCI	(39,000)	(52,000)	(79,000)	(104,000)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(39,000)	(52,000)	(79,000)	(104,000)
Balance at the end of the period	1,080,000	1,360,000	1,080,000	1,360,000
Ownership Share of Equity Method Investees’ Other Comprehensive Income (Loss)
Changes in accumulated other comprehensive income (loss)
Balance at the beginning of the period	605,000	1,262,000	1,537,000	771,000
Other comprehensive income (loss) before reclassifications	(3,674,000)	2,982,000	(4,606,000)	3,473,000
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(3,674,000)	2,982,000	(4,606,000)	3,473,000
Balance at the end of the period	(3,069,000)	4,244,000	(3,069,000)	4,244,000
Forward Contracts [Member]
Changes in accumulated other comprehensive income (loss)
Balance at the beginning of the period	(1,944,000)		1,003,000
Other comprehensive income (loss) before reclassifications	(1,742,000)		(5,193,000)
Amounts reclassified out of AOCI	972,000		1,476,000
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(770,000)	$ 0	(3,717,000)	$ 0
Balance at the end of the period	$ (2,714,000)		$ (2,714,000)