XML 61 R50.htm IDEA: XBRL DOCUMENT v3.21.1
Fair Value Measurements - Fair Value of Financial Instruments (Details) - USD ($)
$ in Thousands
Mar. 31, 2021
Dec. 31, 2020
Fair Value Measurements    
Total $ 2,774 $ 2,879
Level 1 [Member]    
Fair Value Measurements    
Total
Level 2 [Member]    
Fair Value Measurements    
Total 2,774 2,879
Level 3 [Member]    
Fair Value Measurements    
Total
Corporate bonds and notes [Member]    
Fair Value Measurements    
Total 1,028 1,338
Corporate bonds and notes [Member] | Level 1 [Member]    
Fair Value Measurements    
Total
Corporate bonds and notes [Member] | Level 2 [Member]    
Fair Value Measurements    
Total 1,028 1,338
Corporate bonds and notes [Member] | Level 3 [Member]    
Fair Value Measurements    
Total
Municipal bonds [Member]    
Fair Value Measurements    
Total 1,746 1,541
Municipal bonds [Member] | Level 1 [Member]    
Fair Value Measurements    
Total
Municipal bonds [Member] | Level 2 [Member]    
Fair Value Measurements    
Total 1,746 1,541
Municipal bonds [Member] | Level 3 [Member]    
Fair Value Measurements    
Total