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

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Balance Sheet Account Detail (Financial Instruments Not Recorded at Fair Value on a Recurring Basis) (Details) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018	Aug. 09, 2018	Nov. 02, 2015
Debt Instrument [Line Items]
Carrying value	$ 176,993	$ 198,078
Fair value	187,556	168,626
Term loan facility
Debt Instrument [Line Items]
Carrying value	136,803	117,880
Fair value	136,886	116,916
Convertible notes
Debt Instrument [Line Items]
Carrying value	35,909	75,917
Fair value	49,318	50,489
Other debt
Debt Instrument [Line Items]
Carrying value	4,281	4,281
Fair value	$ 1,352	$ 1,221
Convertible Senior Notes Due 2020
Debt Instrument [Line Items]
Debt instrument, stated interest rate			3.25%
Convertible Senior Notes Due 2020 \| Convertible notes
Debt Instrument [Line Items]
Debt instrument, stated interest rate				3.25%