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

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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ 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 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Face (par) amount of the original debt instrument that was repurchased.

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The cash outflow from the repayment of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3291-108585

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Schedule of Debt Obligations (Parenthetical) (Detail) - Convertible Notes - USD ($) $ in Millions			9 Months Ended
	Jun. 01, 2016	Mar. 18, 2013	Sep. 30, 2016	Jul. 31, 2016	Jun. 30, 2016	Apr. 30, 2016	Apr. 04, 2016	Dec. 31, 2015	Sep. 30, 2015	May 23, 2011
1.50% Senior Subordinated Notes Due March 15, 2018
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		1.50%	1.50%					1.50%	1.50%
Debt instrument, par value of notes repurchased			$ 104.9	$ 53.2	$ 51.7
Debt instrument, maturity date		Mar. 15, 2018
2.50% Senior Subordinated Notes Due June 2016
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			2.50%				2.50%	2.50%	2.50%	2.50%
Debt instrument, par value of notes repurchased						$ 143.9
Repayment of remaining outstanding balance of convertible notes upon maturity	$ 156.1
Debt instrument, maturity date			Jun. 01, 2016