Benefit Plans (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Benefit Plans [Abstract]
Employer contributions	$ 0	$ 0	$ 0
Expense related to new 401(k) plan	700,000	$ 500,000
Stop loss coverage on self-insured plan	$ 100,000