Significant Accounting Policies and Practices - Sale of Business (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017	Sep. 30, 2015	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash consideration received			$ 0.6	$ 0.0
Security business | Disposed of by sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gross sale price		$ 1.8
Net gain on sale of business		0.5
Cash consideration received		$ 1.0
Period of business performance and retention of current customers for payment of contingent consideration		18 months
Fair value of contingent consideration receivable		$ 0.5			$ 0.5
Additional earn out of contingent consideration	$ 0.1		$ 0.1
Total earn out of contingent consideration	$ 0.6