Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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Period Type:	instant

- Definition

Shares Exercisable Upon Conversion

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

The cash inflow provided by derivative instruments during the period, which are classified as financing activities, excluding those designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3505-108585

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Convertible Senior Notes - Note Hedges (Details) - USD ($) $ in Thousands, shares in Millions	1 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Jun. 30, 2012
Debt Instrument [Line Items]
Proceeds from settlement of bond hedges related to convertible senior notes		$ 100,459	$ 0	$ 0
Interest Rate Contract [Member]
Debt Instrument [Line Items]
Aggregate amount of hedge					$ 58,200
Shares exercisable upon conversion					2
Senior Notes [Member] \| Convertible Senior Notes Due 2017 [Member]
Debt Instrument [Line Items]
Debt, aggregate principal amount repurchased	$ 220,000
Proceeds from settlement of bond hedges related to convertible senior notes	$ 100,500