Significant Accounting Policies (Goodwill and Other Intangible Assets) (Details) (USD $)			3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014 Provider Networks [Member]	Dec. 31, 2013 Provider Networks [Member]	Mar. 31, 2014 Customer Relationships and Other [Member]	Dec. 31, 2013 Customer Relationships and Other [Member]	Mar. 31, 2014 Western Region Operations [Member]	Dec. 31, 2013 Western Region Operations [Member]	Jun. 30, 2013 Western Region Operations [Member]
Goodwill [Line Items]
Goodwill	$ 565,886,000	$ 565,886,000					$ 565,900,000	$ 565,900,000
Ratio of fair value to carrying value									149.00%
Finite-Lived Intangible Assets
Gross Carrying Amount	71,000,000	70,000,000	41,500,000	40,500,000	29,500,000	29,500,000
Accumulated Amortization	(57,100,000)	(56,200,000)	(36,000,000)	(35,700,000)	(21,100,000)	(20,500,000)
Net Balance	13,900,000	13,800,000	5,500,000	4,800,000	8,400,000	9,000,000
Weighted Average Life (in years)			18 years 10 months 24 days	19 years 4 months 24 days	11 years 1 month 6 days	11 years 1 month 6 days
Future Amortization Expense, Current to Five Succeeding Fiscal Years
2014	3,000,000
2015	2,800,000
2016	2,200,000
2017	2,200,000
2018	$ 2,100,000