Identified Intangible Assets and Goodwill, Net (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Identified intangible assets, gross	$ 35,282	$ 34,798
Accumulated amortization	29,070	28,604
Identified intangible assets, net	6,212	6,194
Goodwill	35,163	35,477
Identified intangible assets and goodwill, net	41,375	41,671
Goodwill, Purchase Accounting Adjustments	298
Amortization of Intangible Assets	52
Finite-Lived Intangible Assets, Purchase Accounting Adjustments	70
Customer lists/relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Identified intangible assets, gross	21,972	21,487
Accumulated amortization	17,186	16,846
Employment-related [Member]
Finite-Lived Intangible Assets [Line Items]
Identified intangible assets, gross	7,332	7,333
Accumulated amortization	6,691	6,624
Tradenames [Member]
Finite-Lived Intangible Assets [Line Items]
Identified intangible assets, gross	5,978	5,978
Accumulated amortization	$ 5,193	$ 5,134