Borrowings - Convertible Senior Unsecured Notes (Details) - Convertible Debt - 6.75% Convertible Senior Unsecured Notes	1 Months Ended
Oct. 31, 2017 USD ($) $ / shares
Debt Instrument [Line Items]
Aggregate principal amount of 6.75% convertible senior unsecured notes	$ 115,000,000
Interest rate, stated percentage	6.75%
Convertible notes, carrying amount of equity component	$ 15,000,000
Proceeds from issuance of long-term debt	$ 111,100,000
Convertible senior unsecured notes, earliest redemption period by company	3 months
Redemption price, percentage	100.00%
Convertible senior unsecured notes, conversion ratio	0.0831947
Convertible senior unsecured notes, conversion price (in dollars per share) \| $ / shares	$ 12.02

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
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-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

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

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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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- Definition

Face (par) amount of debt instrument at time of issuance.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
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- Definition

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

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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.

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- Definition

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

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- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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Debt Instrument, Convertible, Earliest Redemption Period By Company

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Debt Instrument, Convertible, Underwriter Overallotment, Amount

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