Amount of noncash expense included in interest expense to issue debt and obtain financing associated with the related debt instruments. Alternate captions include noncash interest expense.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section S99
-Paragraph 2
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 8
-Article 9

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Net amount of long-term deferred finance costs capitalized at the end of the reporting period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 30
-Section 45
-Paragraph 3
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Debt - Deferred Financing Costs (Details Textual) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Feb. 03, 2015
Debt Instrument [Line Items]
Deferred financing costs related to convertible notes				$ 5.9
Amortization expenses of deferred financing costs included in Interest expense	$ 1.9	$ 2.5	$ 2.6
Weighted-average interest rate on debt borrowings	6.00%	6.00%	5.00%
2015 Credit Agreement
Debt Instrument [Line Items]
Deferred financing costs related to convertible notes	$ 4.7
Senior Subordinated Convertible Notes 2010
Debt Instrument [Line Items]
Deferred financing costs related to convertible notes	$ 0.7