Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Level 3 Inputs) (Details) - Other assets and (liabilities) - USD ($) $ in Thousands |
3 Months Ended | |
---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
|
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ||
Balance at beginning of the period | $ (2,952) | $ (13,004) |
Total realized and unrealized gains | ||
Purchases | (34) | (202) |
Balance at end of the period | (2,780) | (12,135) |
Other income (loss) | ||
Total realized and unrealized gains | ||
Included in other (loss) income | $ 206 | $ 1,071 |