Acquisitions (Narratives) (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2015 USD ($) PercentItemType $ / shares	Dec. 31, 2014 USD ($)	Dec. 31, 2015 USD ($) PercentItemType $ / shares	Dec. 31, 2014 USD ($)	Mar. 31, 2015 USD ($)
Business Acquisition [Line Items]
Stated interest rate percentage	7.875%		7.875%
Supplemental Deferred Purchase Price			$ 4,609,000	$ 5,431,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life			18 years
Restricted Cash and Cash Equivalents, Current	$ 822,000		$ 822,000
Restricted Cash and Cash Equivalents, Noncurrent	4,609,000		4,609,000
Purchase of business, net of cash acquired	5,746,000				$ 150,000
Business Acquisition Purchase Price Allocation Total Allocated	182,467,000		182,467,000
Business Acquisition, Period Results Included in Combined Entity	10,958,000	$ 12,615,000	28,761,000	$ 41,756,000
Line of Credit Facility, Maximum Borrowing Capacity	75,000,000		75,000,000
Proceeds from Secured Lines of Credit	195,000,000
Repayments of Lines of Credit	30,000,000
Goodwill	$ 181,991,000		$ 181,991,000		$ 121,461,000
Business Combination, Separately Recognized Transactions [Domain]
Business Acquisition [Line Items]
Business Acquisition, Share Price | $ / shares	$ 50.00		$ 50.00
Stahlhammer Bommern GmbH [Member]
Business Acquisition [Line Items]
Business Acquisition, Revenue Reported by Acquired Entity for Last Annual Period			$ 16,000,000
Goodwill	$ 7,818,000		7,818,000
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	25,423,000		25,423,000
Goodwill	(1,669,000)		(1,669,000)
STB [Member]
Business Acquisition [Line Items]
Fair Value Inputs, Royalty Rate					10.00%
Business Combination, Consideration Transferred, Other			822,000
Fair Value Inputs, Royalty Rate					1.00%
Other Current Liabilities [Member]
Business Acquisition [Line Items]
Business Combination, Contingent Consideration, Liability	822,000		822,000
Other Noncurrent Liabilities [Member]
Business Acquisition [Line Items]
Business Combination, Contingent Consideration, Liability	4,609,000		$ 4,609,000
Magnetek [Member]
Business Acquisition [Line Items]
Fair Value Inputs, Royalty Rate			5.00%
Fair Value Inputs, Royalty Rate			2.50%
Business Acquisition, Revenue Reported by Acquired Entity for Last Annual Period			$ 112,000,000
Weighted Average Discount Rate, Percent			11.60%
Revenues	29,452,000		$ 39,628,000
Business Acquisition, Period Results Included in Combined Entity	3,847,000		3,255,000
Severance Costs			2,300,000
Goodwill	61,921,000		$ 61,921,000
Goodwill, Other Changes	7,139,000
Customer relationships
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life			17 years
Customer relationships | STB [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	1,227,000		$ 1,227,000		$ 2,957,000
Customer relationships | Magnetek [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	41,000,000		41,000,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles	10,700,000
Trademarks and Trade Names [Member] | STB [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles					1,301,000
Trademarks and Trade Names [Member] | Magnetek [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	26,600,000		26,600,000
Noncompete Agreements [Member] | STB [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles					221,000
Order or Production Backlog [Member] | STB [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles					74,000
Patents [Member] | STB [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles					82,000
Patents [Member] | Magnetek [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles					9,750,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles	310,000
Contingent Consideration Classified as Equity [Member] | STB [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	810,000		810,000		982,000
Tax expense | STB [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	368,000		368,000
Unpatented Technology [Member] | Business Combination, Separately Recognized Transactions [Domain]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles					28,488,000
In Process Research and Development [Member] | Magnetek [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	160,000		$ 160,000
Property, Plant and Equipment [Member] | Magnetek [Member]
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles	1,029,000
Minimum [Member] | Magnetek [Member]
Business Acquisition [Line Items]
Fair Value Inputs, Royalty Rate			3.50%
Minimum [Member] | Contingent Consideration Classified as Equity [Member] | STB [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles					0
Maximum [Member]
Business Acquisition [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	225,000,000		$ 225,000,000
Maximum [Member] | Magnetek [Member]
Business Acquisition [Line Items]
Fair Value Inputs, Royalty Rate			5.00%
Maximum [Member] | Contingent Consideration Classified as Equity [Member] | STB [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles					3,681,000
Other | Contingent Consideration Classified as Equity [Member] | STB [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	$ 13,000		$ 13,000		172,000
Fair Value, Measurements, Nonrecurring [Member] | Significant unobservable Inputs (Level 3) | STB [Member]
Business Acquisition [Line Items]
Fair Value Inputs, Volatility Factor for Contingent Consideration | PercentItemType	0.450		0.450
Fair Value Inputs, Discount Rate for Contingent Consideration | PercentItemType	0.03		0.03
Subordinated Debt [Member]
Business Acquisition [Line Items]
Stated interest rate percentage	7.875%		7.875%
Magnetek [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	$ 190,672,000		$ 190,672,000
Goodwill	61,921,000		61,921,000
Stahlhammer Bommern GmbH [Member]
Business Acquisition [Line Items]
Goodwill, Not Allocated, Amount					1,669,000
Goodwill					$ 7,818,000
Incremental facility [Member]
Business Acquisition [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 75,000,000		$ 75,000,000