Fair Value Of Financial Instruments (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016 USD ($) agreement	Sep. 30, 2016 USD ($) agreement	Dec. 31, 2015 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Notional amount of interest rate swap agreements	$ 275,000	$ 275,000
Interest rate cash flow hedge to be reclassified within next 12 months, net	2,900	2,900
Other comprehensive income (loss) - change in value of interest rate swaps	1,900	(1,284)
Interest expense reclassified from other comprehensive loss	800	2,600
Term loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Term Loan	275,000	275,000
Level 2 \| Accounts payable and accrued expenses \| Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value of interest rate swaps	$ 5,400	$ 5,400
Interest Rate Swap
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Number of interest rate swap agreements \| agreement	2	2
Interest Rate Swap \| Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value of interest rate swaps	$ 5,394	$ 5,394	$ 4,110
Interest Rate Swap \| Fair Value, Measurements, Recurring \| Term loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Interest rate of variable portion of Term loan	1.72%	1.72%
Interest Rate Swap \| Level 2 \| Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value of interest rate swaps	$ 5,394	$ 5,394	$ 4,110

Fixed interest rate related to the interest rate derivative.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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

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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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The amount of net gains or losses on interest rate cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount of long-term notes payable classified as other.

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