Stockholders' Equity - Restricted Stock (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Equity [Abstract]
Number of restricted stock issued	123,564	127,688
Value of restricted stock issued ($ in thousands)	$ 612	$ 351

Aggregate value of stock related to Restricted Stock Awards issued during the period.

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Name:	us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration