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

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Long-Term Debt - Long-Term Debt (Parenthetical) (Detail)	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Convertible Debt [Member] \| 1.75% Senior Notes due 2017 [Member]
Debt Instrument [Line Items]
Interest rate	1.75%	1.75%	1.75%
Senior Notes [Member] \| 7.5% Notes due 2022 [Member]
Debt Instrument [Line Items]
Interest rate	7.50%	7.50%