Convertible Senior Notes, Net - Convertible Senior Notes (Details) - Senior Notes - Convertible Senior Notes Due 2023 $ / shares in Units, $ in Thousands	1 Months Ended	6 Months Ended
Apr. 30, 2019 day	Feb. 28, 2018 USD ($) day $ / shares	Jul. 31, 2019 USD ($)
Debt Instrument [Line Items]
Fixed interest rate		0.25%
Net proceeds from notes		$ 335,000
Initial conversion rate of common stock		0.0206795
Conversion price (in dollars per share) \| $ / shares		$ 48.36
Limitation on sale of common stock (in days) \| day		20
Limitation on sale of common stock due to sale price threshold (in days) \| day	20	30
Threshold percentage of stock price trigger		130.00%	130.00%
Percentage of closing sale price in excess of convertible notes		98.00%
Redemption price percentage		100.00%
Effective interest rate		5.68%
Issuance costs		$ 10,000
Issuance costs attributable to liability component			$ 7,700
Period After Consecutive Trading Days		5 days
Additional Paid-in Capital
Debt Instrument [Line Items]
Issuance costs attributable to equity component			$ 2,320

Debt Instrument, Convertible, Equity Component, Unamortized Discount Issuance Costs

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- Definition

Debt Instrument, Convertible, Period After Consecutive Trading Days

+ References

No definition available.

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- Definition

Percentage Of Closing Sale Price In Excess Of Convertible Notes

+ References

No definition available.

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- Definition

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

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- Definition

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

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- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

+ References

No definition available.

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- Definition

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

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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.

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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.

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- Definition

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

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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.

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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

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

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The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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