Fair Value Disclosures Fair Value Table (Details) - USD ($) $ in Thousands		Mar. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior notes, net	[1]	$ 315,591	$ 320,148
Senior notes, fair value		286,000	292,500
Unsecured revolving credit facility		$ 84,000	$ 67,500

[1] (1) The carrying value for the Senior Notes, as presented at March 31, 2019, is net of the unamortized discount of $1.5 million, unamortized premium of $1.2 million, and unamortized debt issuance costs of $4.1 million. The carrying value for the Senior Notes, as presented at December 31, 2018, is net of the unamortized discount of $1.7 million, unamortized premium of $1.3 million, and unamortized debt issuance costs of $4.5 million. The unamortized discount, unamortized premium and debt issuance costs are not factored into the estimated fair value.