Commitments, Contingencies And Legal Proceedings (Details) - USD ($) $ in Thousands	12 Months Ended			48 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2019
Loss Contingencies [Line Items]
Operating leases rent expense	$ 10,800	$ 12,000	$ 12,000
Operating leases sub-lease proceeds	200	300	$ 300
Stop loss insurance for workers compensation claims per incident	300
Stop loss insurance health care benefit claims per incident	200
Accrual for estimated claims exposure	2,100	1,900
Accrual for workers’ compensation estimated claims exposure	4,400	5,100
Goodwill	$ 45,428	$ 45,794
Minimum [Member] | Expected [Member]
Loss Contingencies [Line Items]
Operating leases sub-lease proceeds				$ 100
Maximum [Member] | Expected [Member]
Loss Contingencies [Line Items]
Operating leases sub-lease proceeds				$ 200