Debt with Commercial Bank (Narrative) (Details)				3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 17, 2016 USD ($) Companies	Oct. 08, 2015 USD ($)	Aug. 05, 2014 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2017	Dec. 31, 2015 USD ($)	Oct. 14, 2015 USD ($)	Feb. 03, 2015 USD ($)	Apr. 26, 2012 USD ($)
Line of Credit Facility [Line Items]
Document Period End Date						Jun. 30, 2016
Proceeds from Lines of Credit					$ 15,000,000	$ 35,000,000
Principal payments of debt obligations						(600,000)	$ (623,000)
Deferred Costs, Current					136,000	136,000			$ 0
Deferred Costs, Noncurrent					537,000	537,000			$ 0
Secured Syndicated Credit Facility, Second Amendment [Member] | Regions Bank [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 400,000,000
Credit agreement, maximum borrowing capacity	$ 500,000,000
Number of Participating Banks | Companies	11
Newly Added Number of Participating Banks | Companies	7
Deferred Costs, Credit Card Origination Costs, Amount					3,560,000	3,560,000
Secured Syndicated Credit Facility, Second Amendment [Member] | Secured Term Loan [Member] | Regions Bank [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 125,000,000
Line of Credit Facility, Term	5 years
Debt Instrument, Periodic Payment, Principal						0
Loans Payable					125,000,000	125,000,000
Loans Payable, Current					12,500,000	12,500,000
Line of Credit Facility, Short Term								12 months
Line of Credit Facility, Periodic Payment, Principal				$ 3,130,000
Short-term Debt					12,500,000	12,500,000
Long-term Debt, Gross					112,500,000	112,500,000
Deferred Costs, Credit Card Origination Costs, Amount					$ 673,000	$ 673,000
Line of credit, interest rate at period end					2.75%	2.75%
Deferred Costs, Current					$ 136,000	$ 136,000
Deferred Costs, Noncurrent					537,000	537,000
Secured Syndicated Credit Facility, Second Amendment [Member] | Revolving Credit Facility [Member] | Regions Bank [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 275,000,000
Line of Credit Facility, Fair Value of Amount Outstanding	$ 104,000,000
Line of Credit Facility, Term	5 years
Deferred Costs, Credit Card Origination Costs, Amount					$ 2,900,000	$ 2,900,000
Line of credit, interest rate at period end					2.75%	2.75%
Secured Syndicated Credit Facility [Member] | Regions Bank [Member]
Line of Credit Facility [Line Items]
Debt instrument, face amount			$ 150,000,000
Debt Instrument, Term			5 years
Secured Syndicated Credit Facility [Member] | Citi Bank [Member]
Line of Credit Facility [Line Items]
Debt instrument, face amount												$ 100,000,000
Secured Syndicated Credit Facility [Member] | Revolving Credit Facility [Member] | Regions Bank [Member]
Line of Credit Facility [Line Items]
Line of Credit, Accordion										$ 50,000,000
Debt Instrument, Term			5 years
Credit agreement, maximum borrowing capacity			$ 200,000,000
Number of Participating Banks		4
Line of Credit Facility, Expansion			50,000,000
Credit agreement, amount outstanding					$ 119,038,000	$ 119,038,000
Secured Syndicated Credit Facility [Member] | Revolving Credit Facility [Member] | Citi Bank [Member]
Line of Credit Facility [Line Items]
Credit agreement, average amount outstanding during period						209,600,000
Credit agreement, maximum amount outstanding during period						$ 226,500,000
Secured Syndicated Credit Facility, First Amendment [Member] | Regions Bank [Member]
Line of Credit Facility [Line Items]
Debt instrument, face amount			150,000,000								$ 190,000,000
Line of Credit, Accordion											50,000,000
Line of Credit Facility, Expansion											90,000,000
Secured Syndicated Credit Facility, First Amendment [Member] | Revolving Credit Facility [Member] | Regions Bank [Member]
Line of Credit Facility [Line Items]
Credit agreement, maximum borrowing capacity			$ 200,000,000							$ 240,000,000	$ 240,000,000