Non-GAAP Measures (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Reconciliation of adjusted net income to net income
Adjusted Net Income	$ 11,030	$ 31,480	$ 38,336	$ 59,538
Adjusted for acquisitions starting in 2013
Amortization of acquired intangibles	(3,426)		(5,059)
Stock compensation relating to acquisitions	(6,373)		(7,311)
Tax impact	3,755		4,740
Net income attributable to Magellan Health, Inc.	$ 4,986	$ 31,480	$ 30,706	$ 59,538
Reconciliation of adjusted EPS to EPS
Adjusted EPS (in dollars per share)	$ 0.39	$ 1.15	$ 1.37	$ 2.17
Adjusted for acquisitions starting in 2013
Amortization of acquired intangibles (in dollars per share)	$ (0.12)		$ (0.18)
Stock compensation relating to acquisitions (in dollars per share)	$ (0.23)		$ (0.26)
Tax impact (in dollars per share)	$ 0.14		$ 0.17
Net income per common share attributable to Magellan Health, Inc. - Diluted	$ 0.18	$ 1.15	$ 1.10	$ 2.17