Additional proceeds receivable on milestone achievements.

No definition available.

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- Definition

Equity method investments, number of commonly interconnected power grids.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Milestone achievement period.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Percentage of outstanding common stock.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Original amount of cost-method investments at the acquisition date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

This element represents the aggregate cost of investments accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

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Period Type:	instant

- Definition

This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (c)-(e)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7(c),9(a))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27405-111563

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e25351-111560

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Minority Investments - Additional Information (Detail)		3 Months Ended	6 Months Ended
Minority Investments - Additional Information (Detail)	Oct. 06, 2015 USD ($)	Jun. 30, 2015 USD ($)	Sep. 30, 2015 USD ($) Item	Sep. 30, 2014 USD ($)
Schedule Of Equity Method Investments [Line Items]
Net proceeds from sale of ownership interest			$ (356,000)	$ (410,000)
Tres Amigas
Schedule Of Equity Method Investments [Line Items]
Number of commonly interconnected power grids \| Item			3
Equity method investment, aggregate cost			$ 5,400,000
Percentage of ownership interest hold			26.00%
Impairment charge on investment		$ 700,000	$ 746,000
Net proceeds from sale of ownership interest			$ (356,000)
Blade Dynamics Ltd
Schedule Of Equity Method Investments [Line Items]
Percentage of ownership interest hold			12.00%
Impairment charge on investment				$ 3,500,000
Cost method investment, original cost			$ 8,000,000
Blade Dynamics Ltd \| Subsequent Event
Schedule Of Equity Method Investments [Line Items]
Percentage of outstanding common stock	100.00%
Net proceeds from sale of ownership interest	$ 2,500,000
Milestone achievement period	3 years
Blade Dynamics Ltd \| Maximum \| Subsequent Event
Schedule Of Equity Method Investments [Line Items]
Additional proceeds receivable upon successful achievement of certain milestones	$ 1,600,000