Financial Services (Narrative) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Financial Services [Line Items]
Mortgage loans in process	$ 30,500	$ 10,000
Mortgage loans held for sale	62,440	$ 52,327
Mortgage loans held for sale aggregate outstanding principal balance	$ 60,000
Weighted Average [Member]
Financial Services [Line Items]
Interest rate	4.80%	4.20%