SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) loan	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Carrying amount of mortgages	$ 83,248	$ 81,056	$ 75,740	$ 103,440
SBA 7(a) Loans
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Number of loans | loan	187
Carrying amount of mortgages	$ 83,248
Principal amount of loans subject to deliquent principal or interest	130
Loans not secured by real estate	84
Loans with subordinate lien positions	373
Federal income tax cost basis of mortgage loans (unaudited)	66,269
SBA 7(a) Loans | Government guaranteed portions
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Carrying amount of mortgages	11,328
Principal amount of loans subject to deliquent principal or interest	0
SBA 7(a) Loans | SBA 7(a) loans receivable, subject to secured borrowings
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Carrying amount of mortgages	15,765
Principal amount of loans subject to deliquent principal or interest	0
SBA 7(a) Loans | General reserves
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Reserves	(426)
Principal amount of loans subject to deliquent principal or interest	0
Reserves	$ 426
SBA 7(a) Loans | Indiana
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Number of loans | loan	20
Carrying amount of mortgages	$ 9,118
Principal amount of loans subject to deliquent principal or interest	0
SBA 7(a) Loans | Indiana | Minimum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 40
Interest Rate	6.75%
SBA 7(a) Loans | Indiana | Maximum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 1,010
Interest Rate	8.00%
SBA 7(a) Loans | Ohio
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Number of loans | loan	24
Size of loans	$ 0
Carrying amount of mortgages	7,433
Principal amount of loans subject to deliquent principal or interest	$ 0
SBA 7(a) Loans | Ohio | Minimum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Interest Rate	7.00%
SBA 7(a) Loans | Ohio | Maximum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 810
Interest Rate	8.00%
SBA 7(a) Loans | Texas
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Number of loans | loan	24
Carrying amount of mortgages	$ 6,632
Principal amount of loans subject to deliquent principal or interest	0
SBA 7(a) Loans | Texas | Minimum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 0
Interest Rate	6.13%
SBA 7(a) Loans | Texas | Maximum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 1,090
Interest Rate	8.00%
SBA 7(a) Loans | Michigan
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Number of loans | loan	22
Carrying amount of mortgages	$ 5,755
Principal amount of loans subject to deliquent principal or interest	0
SBA 7(a) Loans | Michigan | Minimum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 10
Interest Rate	7.00%
SBA 7(a) Loans | Michigan | Maximum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 530
Interest Rate	8.00%
SBA 7(a) Loans | Florida
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Number of loans | loan	11
Carrying amount of mortgages	$ 4,205
Principal amount of loans subject to deliquent principal or interest	0
SBA 7(a) Loans | Florida | Minimum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 0
Interest Rate	7.00%
SBA 7(a) Loans | Florida | Maximum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 1,120
Interest Rate	8.00%
SBA 7(a) Loans | Pennsylvania
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Number of loans | loan	6
Carrying amount of mortgages	$ 3,152
Principal amount of loans subject to deliquent principal or interest	0
SBA 7(a) Loans | Pennsylvania | Minimum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 300
Interest Rate	7.00%
SBA 7(a) Loans | Pennsylvania | Maximum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 760
Interest Rate	8.00%
SBA 7(a) Loans | Virginia
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Number of loans | loan	6
Carrying amount of mortgages	$ 2,004
Principal amount of loans subject to deliquent principal or interest	0
SBA 7(a) Loans | Virginia | Minimum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 40
Interest Rate	6.75%
SBA 7(a) Loans | Virginia | Maximum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 780
Interest Rate	8.00%
SBA 7(a) Loans | South Carolina
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Number of loans | loan	4
Carrying amount of mortgages	$ 1,950
Principal amount of loans subject to deliquent principal or interest	0
SBA 7(a) Loans | South Carolina | Minimum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 290
Interest Rate	7.00%
SBA 7(a) Loans | South Carolina | Maximum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 790
Interest Rate	8.00%
SBA 7(a) Loans | Wisconsin
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Number of loans | loan	8
Carrying amount of mortgages	$ 1,417
Principal amount of loans subject to deliquent principal or interest	130
SBA 7(a) Loans | Wisconsin | Minimum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 0
Interest Rate	6.25%
SBA 7(a) Loans | Wisconsin | Maximum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 540
Interest Rate	8.00%
SBA 7(a) Loans | Illinois
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Number of loans | loan	5
Carrying amount of mortgages	$ 1,413
Principal amount of loans subject to deliquent principal or interest	0
SBA 7(a) Loans | Illinois | Minimum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 60
Interest Rate	7.00%
SBA 7(a) Loans | Illinois | Maximum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 550
Interest Rate	8.00%
SBA 7(a) Loans | Colorado
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Number of loans | loan	4
Carrying amount of mortgages	$ 1,327
Principal amount of loans subject to deliquent principal or interest	0
SBA 7(a) Loans | Colorado | Minimum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 70
Interest Rate	6.75%
SBA 7(a) Loans | Colorado | Maximum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 550
Interest Rate	8.00%
SBA 7(a) Loans | Mississippi
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Number of loans | loan	4
Carrying amount of mortgages	$ 1,194
Principal amount of loans subject to deliquent principal or interest	0
SBA 7(a) Loans | Mississippi | Minimum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 120
Interest Rate	7.25%
SBA 7(a) Loans | Mississippi | Maximum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 520
Interest Rate	8.00%
SBA 7(a) Loans | Kentucky
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Number of loans | loan	5
Carrying amount of mortgages	$ 922
Principal amount of loans subject to deliquent principal or interest	0
SBA 7(a) Loans | Kentucky | Minimum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 100
Interest Rate	6.50%
SBA 7(a) Loans | Kentucky | Maximum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 280
Interest Rate	8.00%
SBA 7(a) Loans | Other
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Number of loans | loan	44
Carrying amount of mortgages	$ 10,059
Principal amount of loans subject to deliquent principal or interest	0
SBA 7(a) Loans | Other | Minimum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 10
Interest Rate	6.92%
SBA 7(a) Loans | Other | Maximum
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 640
Interest Rate	8.00%
Mortgage Loans - $129,000 | SBA 7(a) Loans | Wisconsin
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 129
Interest Rate	6.25%
Reserves	$ (129)
Reserves	129
Mortgage Loans - $460,000 | SBA 7(a) Loans
SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE
Size of loans	$ 460
Interest Rate	6.50%
Reserves	$ (147)
Reserves	$ 147