Fair Value Measurements (Narrative) (Details)  | 
3 Months Ended | 
|---|---|
| 
 Mar. 31, 2020  
USD ($) 
 | |
| Fair Value Measurements [Abstract] | |
| Transfers between levels | $ 0 | 
| X | ||||||||||
- Definition Amount of transfer of financial instrument between levels of the fair value hierarchy. No definition available. 
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| X | ||||||||||
- References No definition available. 
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