Comprehensive Income (Loss) and Accumulated Other Comprehensive Income (Details) (USD $)	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Accumulated other comprehensive income (loss)
Balance at the beginning of the period	$ 7,694,000	$ 12,020,000
Other comprehensive income (loss) before reclassifications	1,621,000	(7,966,000)
Amounts reclassified out of AOCI	105,000	173,000
Other comprehensive income (loss)	1,726,000	(7,793,000)
Balance at the end of the period	9,420,000	4,227,000
Foreign Currency Translation
Accumulated other comprehensive income (loss)
Balance at the beginning of the period	13,538,000	18,107,000
Other comprehensive income (loss) before reclassifications	2,272,000	(7,966,000)
Other comprehensive income (loss)	2,272,000	(7,966,000)
Balance at the end of the period	15,810,000	10,141,000
Defined Benefit Pension Plans, Net of Tax
Accumulated other comprehensive income (loss)
Balance at the beginning of the period	(7,662,000)	(8,082,000)
Amounts reclassified out of AOCI	175,000	102,000
Other comprehensive income (loss)	175,000	102,000
Balance at the end of the period	(7,487,000)	(7,980,000)
Tax effect of accumulated other comprehensive income (loss)	2,300,000	2,600,000
Post-Retirement Benefit Plans
Accumulated other comprehensive income (loss)
Balance at the beginning of the period	1,818,000	1,995,000
Amounts reclassified out of AOCI	(70,000)	71,000
Other comprehensive income (loss)	(70,000)	71,000
Balance at the end of the period	1,748,000	2,066,000
Share of Equity Method Investees' Other Comprehensive Income (Loss)
Accumulated other comprehensive income (loss)
Other comprehensive income (loss) before reclassifications	(651,000)
Other comprehensive income (loss)	(651,000)
Balance at the end of the period	$ (651,000)