Debt (Convertible) (Details) - USD ($) |
Jun. 30, 2019 |
Dec. 31, 2018 |
Jun. 30, 2018 |
May 31, 2018 |
Dec. 31, 2014 |
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| Convertible Notes due 2019 | |||||
| Debt Instrument [Line Items] | |||||
| Face amount | $ 172,500,000 | $ 172,500,000 | $ 172,500,000 | ||
| Interest rate (as a percent) | 1.75% | ||||
| Effective interest rate (as a percent) | 6.00% | 6.00% | |||
| Convertible notes due 2023 | |||||
| Debt Instrument [Line Items] | |||||
| Face amount | $ 345,000,000 | ||||
| Interest rate (as a percent) | 1.75% | ||||
| Effective interest rate (as a percent) | 6.00% |
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- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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. No definition available.
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