Accounting Policies and Pronouncements (Summary of Amortized Costs Basis) (Details) $ in Thousands	Sep. 30, 2020 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Ending balance as of September 30, 2020	$ 448,887
MUD Receivables
Financing Receivable, Allowance for Credit Loss [Line Items]
Ending balance as of September 30, 2020	331,451
SID Receivables
Financing Receivable, Allowance for Credit Loss [Line Items]
Ending balance as of September 30, 2020	60,198
TIF Receivables
Financing Receivable, Allowance for Credit Loss [Line Items]
Ending balance as of September 30, 2020	1,980
Net Investments in Lease Receivable
Financing Receivable, Allowance for Credit Loss [Line Items]
Ending balance as of September 30, 2020	2,946
Notes Receivable
Financing Receivable, Allowance for Credit Loss [Line Items]
Ending balance as of September 30, 2020	$ 52,312