Acquisitions And Channel Partner Arrangements (Narrative) (Details) customer in Thousands			1 Months Ended		3 Months Ended	12 Months Ended
	Nov. 28, 2016 USD ($)	Aug. 01, 2014 USD ($) customer	Jan. 31, 2015 USD ($)	Jul. 31, 2013	Sep. 30, 2015 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Aug. 01, 2016 USD ($)	Jun. 05, 2015 USD ($)
Business Acquisition [Line Items]
Payment for acquisition of client contracts						$ 21,120,000	$ 382,000	$ 0
Amounts borrowed						249,500,000	$ 79,600,000
Debt, maximum allowed borrowing capacity									$ 250,000,000	$ 150,000,000
Ceridian Channel Partner Arrangement
Business Acquisition [Line Items]
Acquisition date				Jul. 01, 2013
Purchase price of acquisition			$ 13,500,000
Conexis
Business Acquisition [Line Items]
Acquisition date		Aug. 01, 2014
Purchase price of acquisition		$ 118,000,000
Number of organizations serviced | customer		16
Purchase Price Adjusted For Working Capital Adjustments		$ 108,000,000
Holdback obligation		$ 10,000,000
Payments for Previous Acquisition					$ 9,400,000
ADP/COBRA/CHSA
Business Acquisition [Line Items]
Payments to acquire businesses, gross	$ 235,000,000
Proceeds from Long-term Lines of Credit						$ 169,900,000