Long-Term Debt - Summary of Convertible Senior Notes (Details) $ / shares in Units, $ in Millions	1 Months Ended	12 Months Ended
Dec. 31, 2009 d	Dec. 31, 2016 USD ($) d $ / shares
Debt Instrument [Line Items]
Threshold trading days \| d	5
2.25% Convertible Subordinated Debentures [Member]
Debt Instrument [Line Items]
Debt instrument interest rate stated percentage		2.25%
Common stock conversion rate		38.4615
Conversion price per share (in USD per share) \| $ / shares		$ 26.00
Conversion rate of notes to common stock		150.00%
Threshold trading days \| d		20
Consecutive trading days		30 days
Repurchase price, percentage of principal amount		100.00%
Proceeds from issuance of debt		$ 294.2
Effective interest rate		5.80%
Debt issuance costs		$ 5.8
2.25% Convertible Subordinated Debentures [Member] \| Debt Component of Convertible Debt [Member]
Debt Instrument [Line Items]
Debt issuance costs		4.7
2.25% Convertible Subordinated Debentures [Member] \| Equity Component of Convertible Debt [Member]
Debt Instrument [Line Items]
Debt issuance costs		$ 1.1

Conversion Rate Of Notes To Common Stock

No definition available.

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

+ Details

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6509012

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instruments must exceed threshold percentage for a specified number of trading days to trigger conversion feature, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ References

No definition available.

+ Details

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
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- Definition

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

+ References

+ 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

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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-Publisher FASB
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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

No definition available.

+ Details

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- Details

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