Long-Term Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Total debt	$ 809,663	$ 456,900
Financing leases	508	0
Less: Current portion	13,515	18,336
Total long-term debt	796,148	438,564
Revolving line of credit
Debt Instrument [Line Items]
Total debt	262,000	312,000
Term loan, net of deferred debt issuance costs of $1,727 and $311 in 2019 and 2018, respectively
Debt Instrument [Line Items]
Total debt	259,960	144,064
Unamortized debt issuance cost	1,727	311
2.625% convertible notes, net of deferred debt issuance costs of $9,964 and unamortized discount of $47,841 in 2019
Debt Instrument [Line Items]
Convertible Debt	287,195	0
Unamortized debt issuance cost	9,964	0
Unamortized discount	47,841	0
Mortgage notes
Debt Instrument [Line Items]
Total debt	$ 0	$ 836

Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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