Quarterly report pursuant to Section 13 or 15(d)

Restricted Cash Equivalents and Investments (Schedule of Cash Equivalents and Available-for-Sale Securities) (Details)

v3.22.1
Restricted Cash Equivalents and Investments (Schedule of Cash Equivalents and Available-for-Sale Securities) (Details)
Mar. 31, 2022
USD ($)
Schedule of Available-for-sale Securities [Line Items]  
Amortized Cost $ 3,577,000
Gross Unrealized Gains
Gross Unrealized Losses (56,000)
Fair Value 3,521,000
Cash Equivalents 682,000
Short-Term Investments 786,787
Long-Term Investments 2,052,000
Cash and Cash Equivalents [Member]  
Schedule of Available-for-sale Securities [Line Items]  
Amortized Cost 682,000
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value 682,000
Cash Equivalents 682,000
Short-Term Investments
Long-Term Investments
Money Market Funds [Member]  
Schedule of Available-for-sale Securities [Line Items]  
Amortized Cost 682,000
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value 682,000
Cash Equivalents 682,000
Short-Term Investments
Long-Term Investments
Investments [Member]  
Schedule of Available-for-sale Securities [Line Items]  
Amortized Cost 2,895,000
Gross Unrealized Gains
Gross Unrealized Losses (56,000)
Fair Value 2,839,000
Cash Equivalents
Short-Term Investments 787,000
Long-Term Investments 2,052,000
Corporate Notes/Bonds [Member]  
Schedule of Available-for-sale Securities [Line Items]  
Amortized Cost 2,895,000
Gross Unrealized Gains
Gross Unrealized Losses (56,000)
Fair Value 2,839,000
Cash Equivalents
Short-Term Investments 787,000
Long-Term Investments $ 2,052,000