Date that the percentage of debt with a maximum interest rate begins to decrease quarterly

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- Definition

Fixed charge coverage ratio

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Leverage Ratio

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Loan Initiation Amortization Period - Years

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Percentage decrease in amount of debt with maximum interest rate

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Total laquidity

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The net increase(decrease) in interest income during the period representing the allocation of deferred loan origination fees less deferred loan origination costs using the effective interest method over the term of the debt arrangement to which they pertain taking into account the effect of prepayments.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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Nominal or face amount used to calculate payments on the derivative asset.

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Fair value as of the balance sheet date of interest rate derivative assets, net of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet.

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Fair value of the amount outstanding under the credit facility.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Number of interest rate derivative instruments held by the entity at the reporting date.

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Bank Debt (Narrative) (Details)	1 Months Ended	12 Months Ended	21 Months Ended
Bank Debt (Narrative) (Details)	Mar. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) security	Dec. 31, 2017 USD ($) security	Mar. 18, 2016 USD ($)	Mar. 17, 2016 USD ($)
Debt Instrument [Line Items]
Total laquidity		$ 85,000,000	$ 85,000,000
Intererst rate effective percentage		4.57%	4.57%
Fixed charge coverage ratio		190.00%	190.00%
Leverage ratio		240.00%	240.00%
Credit Agreement [Member]
Debt Instrument [Line Items]
Closing costs of debt	$ 9,100,000
Loan initiation amortization period		5 years
Credit agreement, amount outstanding		$ 202,000,000	$ 202,000,000
Borrowing capacity		$ 69,000,000	$ 69,000,000
Debt maturity date		Aug. 01, 2019
Minimum [Member]
Debt Instrument [Line Items]
Fixed charge coverage ratio		125.00%	125.00%
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt, interest rate spread on variable rate		3.00%
London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt, interest rate spread on variable rate		2.25%
London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt, interest rate spread on variable rate		4.00%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt face amount		$ 100,000,000	$ 100,000,000
Intererst rate effective percentage		5.00%	5.00%
Percentage decrease in amount of debt with maximum interest rate per quarter after commencement date			10.00%
Date that the percentage of debt with a maximum interest rate begins to decrease quarterly		Mar. 31, 2016
Revolving Credit Facility [Member] \| Credit Agreement [Member]
Debt Instrument [Line Items]
Credit agreement, amount outstanding		$ 131,000,000	$ 131,000,000
Revolving Credit Facility [Member] \| Credit Agreement [Member] \| PNC Bank [Member]
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity				$ 200,000,000	$ 250,000,000
Term Loan [Member] \| Credit Agreement [Member]
Debt Instrument [Line Items]
Credit agreement, amount outstanding		$ 71,000,000	$ 71,000,000
Debt face amount				$ 175,000,000
Interest Rate Swap [Member]
Debt Instrument [Line Items]
Number of interest rate swaps \| security		2	2
Fair value (liability) of interest rate swaps		$ 500,000	$ 500,000
Interest Rate Swap One [Member]
Debt Instrument [Line Items]
Notional values of interest rate swaps		96,000,000	96,000,000
Interest Rate Swap Two [Member]
Debt Instrument [Line Items]
Notional values of interest rate swaps		$ 30,000,000	$ 30,000,000