Amount of the total principal payments made during the annual reporting period.

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

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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-Topic 210
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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.

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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
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Net Carrying Amount of Debt (Parenthetical) (Detail) - USD ($) $ in Millions				12 Months Ended
	Jun. 01, 2016	Mar. 07, 2016	Mar. 18, 2013	Dec. 31, 2016	Jul. 31, 2016	Jun. 30, 2016	Apr. 30, 2016	Apr. 04, 2016	Dec. 31, 2015	Dec. 31, 2014	May 23, 2011
Convertible Notes \| 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
Convertible Notes \| 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
Senior Secured Term Loan
Debt Instrument [Line Items]
Debt instrument, maturity date		Mar. 07, 2021
Debt instrument, annual principal prepayment				$ 28.7