Long-Lived Assets (Details Textual) $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($)
Client contracts
Finite Lived Intangible Assets [Line Items]
Estimated useful life	38 months
Estimated total amortization expense 2017	$ 16.3
Estimated total amortization expense 2018	12.6
Estimated total amortization expense 2019	7.9
Estimated total amortization expense 2020	3.0
Estimated total amortization expense 2021	$ 0.2
Software
Finite Lived Intangible Assets [Line Items]
Estimated useful life	61 months
Estimated total amortization expense 2017	$ 8.4
Estimated total amortization expense 2018	6.5
Estimated total amortization expense 2019	5.0
Estimated total amortization expense 2020	3.6
Estimated total amortization expense 2021	$ 2.6