Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Subsequent Events - Additional Information (Detail) € in Millions, $ in Millions						3 Months Ended
	Nov. 03, 2016 USD ($)	Oct. 10, 2016 USD ($)	Oct. 10, 2016 EUR (€)	Jul. 23, 2015 USD ($)	Jul. 05, 2011 patent	Dec. 31, 2016 USD ($)
Subsequent Event [Member]
Subsequent Event [Line Items]
Loss on extinguishment of debt						$ 2.2
4.125% Senior Subordinated Notes Due 2026 [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Proceeds from issuance of senior subordinated notes		$ 222.2	€ 200.0
Senior subordinated notes interest rate		4.125%	4.125%
Corning [Member] \| PPC Broadband, Inc. [Member]
Subsequent Event [Line Items]
Gain contingency, number of patents allegedly infringed upon \| patent					2
Litigation settlement, amount				$ 23.9
Corning [Member] \| PPC Broadband, Inc. [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Litigation settlement, amount	$ 47.7