Subsequent Event (Details) - USD ($)	Feb. 23, 2018	Feb. 08, 2018	Jan. 12, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Subsequent Event [Line Items]
Assets				$ 192,659,000	$ 179,678,000	$ 181,336,000
Goodwill				27,144,000	27,144,000	$ 27,144,000
Intangible assets, net				$ 19,804,000	$ 21,394,000
Subsequent Event
Subsequent Event [Line Items]
Proceeds from Divestiture of Businesses			$ 10,600,000
Gain (Loss) on Disposition of Assets			520,000
Dividends declared per share		$ 0.68
Restricted Stock | Subsequent Event
Subsequent Event [Line Items]
Stock Issued During Period, Value, Restricted Stock Award, Gross	$ 9,700,000
Restricted stock issued	169,000
Assets, Total [Member] | Subsequent Event
Subsequent Event [Line Items]
Assets			9,700,000
Goodwill [Member] | Subsequent Event
Subsequent Event [Line Items]
Goodwill			7,300,000
Finite-Lived Intangible Assets [Member] | Subsequent Event
Subsequent Event [Line Items]
Intangible assets, net			$ 2,200,000