Significant Accounting Policies (Health Plan Services Health Care Cost) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Health Care Organization Revenue and Expense [Line Items]
Prior Years Favorable Reserve Development	$ 22,900,000
Health plan services (excluding depreciation and amortization)	2,402,342,000	2,268,736,000
Provision For Adverse Deviation, Release	45,900,000
Provision For Adverse Deviation	57,400,000		53,400,000
Unfavorable Development [Member]
Health Care Organization Revenue and Expense [Line Items]
Health plan services (excluding depreciation and amortization)	$ 23,000,000