Summary of Significant Accounting Policies (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Balance at beginning of period	$ 539	$ 121	$ 246
Charged to expense	3,249us-gaap_ProvisionForDoubtfulAccounts	3,432us-gaap_ProvisionForDoubtfulAccounts	1,728us-gaap_ProvisionForDoubtfulAccounts
Write-offs	(3,329)	(2,433)	(1,853)
Sale of properties	0us-gaap_GainLossOnSaleOfProperties	(581)us-gaap_GainLossOnSaleOfProperties	0us-gaap_GainLossOnSaleOfProperties
Balance at end of period	$ 459	$ 539	$ 121

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

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Amount of direct write-downs of accounts receivable charged against the allowance.

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The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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