Summary of Significant Accounting Policies (Details) - ASU 2016-02 - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Jan. 01, 2016
Recent Accounting Pronouncements
Estimated increase in straight-line rental expense	$ 1.3	$ 1.2
Lease costs in sales and marketing expense	$ 0.5	$ 0.5
Minimum
Recent Accounting Pronouncements
Right of use asset			$ 100.0
Right of use liability			100.0
Maximum
Recent Accounting Pronouncements
Right of use asset			300.0
Right of use liability			$ 300.0