401(k) Profit Sharing Plan (Narrative) (Details) - USD ($)	1 Months Ended	12 Months Ended
	Jan. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Defined Contribution Plan, Employer Matching Contribution, Percent of Match, First One Percent of Contributions		100.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Match, Next Five Percent of Contributions		50.00%
Defined Contribution Plan, Cost Recognized	$ 56,354	$ 1,100,000	$ 1,000,000
Other Than SERP Hired Prior to 2010 [Member]
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent		0.50%
Other Than SERP Hired Since Jan 1 2010 [Member]
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent		4.00%