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2. Acquisitions (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
2. Acquisitions (Details) - USD ($) $ in Millions	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2019	Mar. 04, 2019
Business Combinations [Abstract]
Business Combination, Consideration Transferred		$ 20.0
Payments to Acquire Businesses, Net of Cash Acquired		16.0	$ 4.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles					$ 5.5
Goodwill, Acquired During Period		15.6		$ 15.6
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill					$ 0.2
Business Combination, Consideration Transferred, Liabilities Incurred		$ 1.3
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles	$ 6.5
Goodwill, Purchase Accounting Adjustments	6.3
Goodwill, Translation and Purchase Accounting Adjustments	(1.4)
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Assets	0.2
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Liabilities	$ 1.4