Description of Business (Sale of Fiber Optics-related Assets) (Details) (Sumitomo Electric Industries, LTD, USD $) In Millions, unless otherwise specified	0 Months Ended	3 Months Ended	6 Months Ended
May 07, 2012	Mar. 31, 2013	Mar. 31, 2013
Sumitomo Electric Industries, LTD
Footnote disclosures:
Gain on sale of assets	$ 2.8
Indemnification associated with sale of assets		3.4	3.4
Indemnification period			2 years
Proceeds from sale of assets			13.1
Cash held in escrow		2.6	2.6
Escrow, payout period (in years)			2 years
Deferred gain associated with sale of assets		4.9	4.9
Reduction of purchase price		1.1
Additional gain recognized from sale		0.4
Fees billed under transition services agreement		0.6	1.2
Sale of assets, purchase price adjustment			0.5
Sale of assets, purchase price adjustment, payout period (in months)			12 months
Expenses incurred directly associated with sale of assets			$ 0.6

Amount held in escrow.

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- Definition

Deferred gain on sale of assets that does not qualify for gain recognition as of the balance sheet date.

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Disposal Group, Expenses Incurred Directly Associated With Sale Of Assets.

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Disposal Group, Sales Price Adjustment, Amount

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Disposal Group, Sales Price Adjustment, Payable Term, In Months.

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Period over which escrow deposit is paid to Company; in years.

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Indemnification Period

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Sale of Assets, Additional Gain Recognized from Sale

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Sale of Assets, Reduction of Purchase Price

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Transition services agreement, fees billed during the period.

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In a transaction not treated as a divestiture for accounting purposes and in which the disposed operation is not consolidated for accounting purposes, the aggregate amount of the disposed liabilities that are segregated in the balance sheet.

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- Definition

The gain (loss) resulting from the sale of a disposal group that is not a discontinued operation. It is included in income from continuing operations before income taxes in the income statement.

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- Definition

The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets.

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