Goodwill (Narrative) (Details) (USD $)	3 Months Ended	9 Months Ended
Dec. 31, 2010	Jun. 30, 2011
Reduction to goodwill due to favorable resolution of lease termination recorded in restructuring reserve	$ 103,000	$ 103,000
Goodwill addition		24,188,000
Impairment		0
Weighted average cost of capital assumption		11.30%
Assumed annual compound growth rate after five years		4.40%
Percent increase in discount rate that would not result in impairment		10.00%
Percent decrease in growth rate that would not result in impairment		10.00%
Percent decrease in forecasted cash flow that would not result in impairment		10.00%
Percent increase in discount rate that would result in impairment		11.00%
Percent decrease in growth rate that would result in impairment		38.00%
Percent decrease in forecasted cash flow that would result in impairment		15.00%
Turbine Systems [Member]
Goodwill addition
Electrical Power Systems [Member]
Goodwill addition		$ 24,188,000

The aggregate amount of goodwill acquired in the period and allocated to the reportable segment. The value is stated at fair value based on the purchase price allocation.

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Loss recognized during the period that results from the write-down of goodwill after comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill. Goodwill is assessed at least annually for impairment.

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Reduction to goodwill due to a lease settlement that was favorable in comparison to the previously recorded restructuring reserve accrual established in purchase accounting. This item represents both a credit or reduction to goodwill and a debit or reduction to the restructuring reserve accrual.

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Weighted average cost of capital assumption used to discount forecasted cash flows for the annual goodwill impairment test

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