Debt (Schedule of Lines of Credit Outstanding) (Details) - USD ($) $ in Thousands			12 Months Ended
	Dec. 15, 2015	Jul. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Oct. 13, 2014	Dec. 31, 2013	Oct. 13, 2013
Citibank, N.A. and Credit Suisse AG, CAyman Islands Branch [Member] | Unsecured Debt [Member]
Line of Credit Facility [Line Items]
Borrowings on lines of credit	$ 40,000		$ 30,000	$ 0
Debt Instrument, Basis Spread on Variable Rate	1.50%
Debt Instrument, Interest Rate, Effective Percentage			2.90%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.45%
Unrestricted Cash Borrowing Base Limitation	100.00%
Borrowing Base Limitation for Unrestricted Cash	$ 15,000
Book Value of Model Homes Borrowing Base	85.00%
Book Value of Finished Lots and Land Under Development	65.00%
Book Value of Entitled Land	50.00%
Credit Suisse AG, Cayman Islands Branch [Member] | Unsecured Debt [Member]
Line of Credit Facility [Line Items]
Borrowings on lines of credit	$ 15,000
Citibank, N.A. [Member] | Unsecured Debt [Member]
Line of Credit Facility [Line Items]
Borrowings on lines of credit	25,000
Subsidiary of JBGL | Inwood National Bank
Line of Credit Facility [Line Items]
Borrowings on lines of credit			$ 47,500	14,061
Subsidiary of JBGL | Inwood National Bank | Direct Finance Leases A
Line of Credit Facility [Line Items]
Borrowings on lines of credit			0	662
Line of credit, maximum borrowing capacity						$ 4,800
Stated interest rate						4.00%
Subsidiary of JBGL | Inwood National Bank | Direct Finance Leases B
Line of Credit Facility [Line Items]
Borrowings on lines of credit			0	899
Line of credit, maximum borrowing capacity						$ 3,000
Stated interest rate						4.00%
Subsidiary of JBGL | Inwood National Bank | John's Creek
Line of Credit Facility [Line Items]
Borrowings on lines of credit			0	12,500
Line of credit, maximum borrowing capacity						$ 8,000	$ 25,000
Stated interest rate					4.00%
Subsidiary of JBGL | Inwood National Bank | JohnsCreekCarrolltonAllen [Member]
Line of Credit Facility [Line Items]
Borrowings on lines of credit			17,500	0
Line of credit, maximum borrowing capacity		$ 50,000
BorrowingBaseLimitationTotalValueOfland		50.00%
BorrowingBaseLimitationTotalValueOfLotsOwned		60.00%
MaximumValueOfLandUsedWhenCalculatingBorrowingBase		50.00%
Other Assets
Line of Credit Facility [Line Items]
Debt issuance cost			$ 800	$ 400
Other Assets | Citibank, N.A. and Credit Suisse AG, CAyman Islands Branch [Member] | Unsecured Debt [Member]
Line of Credit Facility [Line Items]
Debt issuance cost	500
Other Assets | Subsidiary of JBGL | Inwood National Bank | JohnsCreekCarrolltonAllen [Member]
Line of Credit Facility [Line Items]
Debt issuance cost		$ 300
Minimum | Subsidiary of JBGL | Inwood National Bank | JohnsCreekCarrolltonAllen [Member]
Line of Credit Facility [Line Items]
Stated interest rate		4.00%
Maximum | Citibank, N.A. and Credit Suisse AG, CAyman Islands Branch [Member] | Unsecured Debt [Member]
Line of Credit Facility [Line Items]
Borrowings on lines of credit	$ 75,000
Maximum | Subsidiary of JBGL | Inwood National Bank | JohnsCreekCarrolltonAllen [Member]
Line of Credit Facility [Line Items]
Stated interest rate		18.00%
Federal Funds Rate [Domain] | Citibank, N.A. and Credit Suisse AG, CAyman Islands Branch [Member] | Unsecured Debt [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.50%
London Interbank Offered Rate (LIBOR) [Member] | Citibank, N.A. and Credit Suisse AG, CAyman Islands Branch [Member] | Unsecured Debt [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.00%
London Interbank Offered Rate (LIBOR) [Member] | Citibank, N.A. and Credit Suisse AG, CAyman Islands Branch [Member] | Unsecured Debt [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.50%