Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended			9 Months Ended
	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2014
Income/(loss) before income taxes [Abstract]
Domestic		$ 37,211	$ 23,068	$ 13,525
International		8,295	21,939	17,843
Income before income taxes		45,506	45,007	31,368
Current [Abstract]
Federal		2,572	630	(177)
State		0	15	4
International		512	5,980	8,525
Current, Total		3,084	6,625	8,352
Deferred [Abstract]
Federal		(14,965)	7,014	(36,287)
International		(746)	1,093	(3,926)
Deferred, Total		(15,711)	8,107	(40,213)
Total		(12,627)	14,732	(31,861)
Statutory federal income tax rate (in hundredths)		35.00%	35.00%	35.00%
Provision for income taxes differs from the statutory federal income tax rate [Abstract]
Income tax provision at U.S federal statutory rate		15,927	15,752	10,979
Effect of foreign income taxed at rates other than the U.S. federal statutory rate		751	242	(451)
Foreign income inclusions		2,742	0	4,563
Tax credits		(2,692)	(250)	(177)
Change in tax laws		0	(1,155)	(1,329)
Tax audit settlements	(3,948)	(3,948)	0	0
Net change in valuation allowance		(26,543)	(97)	(45,105)
Permanent items and other		1,136	240	(341)
Total		(12,627)	14,732	(31,861)
Deferred tax assets [Abstract]
Inventory	3,313	3,313	2,510
Foreign tax credit carryforwards	19,925	19,925	31,463
Environmental	2,993	2,993	2,995
Net operating loss carryforwards (foreign)	3,381	3,381	944
Employee benefits	18,879	18,879	12,841
Research & experimentation tax credit carryforwards	480	480	1,900
Alternative minimum tax credit carryforwards	2,773	2,773	2,773
Property, plant and equipment	3,898	3,898	3,843
Other	5,605	5,605	4,037
Total gross deferred tax assets	61,247	61,247	63,306
Valuation allowances	(5,053)	(5,053)	(29,890)
Total deferred tax assets	56,194	56,194	33,416
Deferred tax liabilities [Abstract]
Property, plant and equipment	(9,649)	(9,649)	(9,059)
Intangibles and other	(10,487)	(10,487)	(9,856)
Unremitted foreign earnings	(726)	(726)	(568)
Foreign tax allocation reserve	(1,856)	(1,856)	(2,006)
Other	(1,978)	(1,978)	(2,187)
Total deferred tax liabilities	(24,696)	(24,696)	(23,676)
Net deferred tax asset	31,498	31,498	9,740
Classified as follows in the consolidated balance sheet: [Abstract]
Current deferred tax asset (included in other current assets)	3,808	3,808	2,874
Non-current deferred tax asset	38,424	38,424	19,799
Current deferred tax liability (included in other current liabilities)	(189)	(189)	(98)
Non-current deferred tax liability	(10,545)	(10,545)	(12,835)
Operating Loss Carryforwards [Line Items]
Foreign earnings repatriated		5,442		8,953
Valuation Allowance [Line Items]
Net change in valuation allowance		(26,543)	(97)	(45,105)
Activity related to the entity's unrecognized tax benefits [Roll Forward]
Balance at January 1		3,922	3,967	4,328	3,922
Gross increases related to current period tax positions		275	257	348
Gross decreases related to prior period tax positions		(1,149)	(427)	(483)
Expirations of statute of limitations for the assessment of taxes		(106)	(37)	(113)
Settlements		(1,113)	0	(175)
Foreign currency translation		(186)	162	62
Balance at December 31	1,643	1,643	3,922	3,967
Unrecognized tax benefits that would affect effective tax rate	1,643	1,643
Gross interest and penalties related to unrecognized tax benefits	489	489	5,005	4,511
Interest and penalties		337	219	985
Income Tax Contingency [Line Items]
Potential future increase/(decrease) to unrecognized tax benefits	250	250
Amount of tax and interest paid as final settlement to the tax authority	1,487	1,487
Decrease in unrecognized tax benifits	4,137
Foreign Valuation Allowance [Member]
Provision for income taxes differs from the statutory federal income tax rate [Abstract]
Net change in valuation allowance		1,923	(48)	(140)
Valuation Allowance [Line Items]
Net change in valuation allowance		1,923	(48)	(140)
Domestic Gains and Losses Included in OCI and Discontinued Operations [Member]
Provision for income taxes differs from the statutory federal income tax rate [Abstract]
Net change in valuation allowance			(2,543)
Valuation Allowance [Line Items]
Net change in valuation allowance			(2,543)
Domestic Valuation Allowance [Member]
Provision for income taxes differs from the statutory federal income tax rate [Abstract]
Net change in valuation allowance		(26,760)	(3)	(47,490)
Valuation Allowance [Line Items]
Net change in valuation allowance		(26,760)	(3)	(47,490)
Foreign Gains and Losses Related to Deferred Taxes and Currency Translation Adjustments Included in OCI [Member]
Provision for income taxes differs from the statutory federal income tax rate [Abstract]
Net change in valuation allowance		1,706	46	18
Valuation Allowance [Line Items]
Net change in valuation allowance		1,706	46	18
Domestic Valuation Allowance Release of Valuation Allowance Due to Profitability [Member]
Provision for income taxes differs from the statutory federal income tax rate [Abstract]
Net change in valuation allowance		26,902		(36,287)
Valuation Allowance [Line Items]
Net change in valuation allowance		26,902		(36,287)
Foreign Valuation Allowance Change for Income Loss [Member]
Provision for income taxes differs from the statutory federal income tax rate [Abstract]
Net change in valuation allowance		217	(94)	(158)
Valuation Allowance [Line Items]
Net change in valuation allowance		217	(94)	(158)
Domestic Valuation Allowance Change for Income Loss [Member]
Provision for income taxes differs from the statutory federal income tax rate [Abstract]
Net change in valuation allowance		142		(8,660)
Valuation Allowance [Line Items]
Net change in valuation allowance		142		(8,660)
Valuation allowance against foreign tax credits [Member]
Provision for income taxes differs from the statutory federal income tax rate [Abstract]
Net change in valuation allowance		11,719			15,183
Valuation Allowance [Line Items]
Net change in valuation allowance		11,719			15,183
Foreign Operating Loss Carryforward [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	11,323	11,323
Foreign Operating Loss Acquired In 2014 [Member]
Operating Loss Carryforwards [Line Items]
Acquired operating loss carryforwards	$ 8,778	$ 8,778