Medicare and Medicaid EHR Incentives (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended				3 Months Ended	6 Months Ended	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011 Restatement adjustment [Member] Change in accounting method [Member]	Dec. 31, 2012 Restatement adjustment [Member] Change in accounting method [Member]	Jun. 30, 2011 Restatement adjustment [Member] Change in accounting method [Member]
Net income (loss) attributable to Vanguard Health Systems, Inc. stockholders	$ 12.2	$ 15.7	$ 26.1	$ (6.0)			$ 3.6	$ 1.1	$ (1.1)
Medicare and Medicaid EHR incentives	14.5	21.3	25.8	24.4
Receivables related to EHR incentives	13.2		13.2			2.7
Deferred revenue related to EHR incentives	$ 7.4		$ 7.4		$ 4.3