Fair Value Measurements (Details) - Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation (Parentheticals) - Fair Value, Recurring [Member] - Fair Value, Inputs, Level 3 [Member] $ in Millions	Dec. 31, 2019 USD ($)
3.25% Convertible Senior Notes Due 2023 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
New issuance face value	$ 29.6
Oasis Management And Oasis Investments ll Master Fund Ltd. [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
New issuance face value	$ 8.0