Fair Value Measurements (Quantitative Information About Level 3 Fair Value Measurements) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Goodwill	$ 558,886	$ 558,886
Western Region Operations [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Goodwill	558,900	558,900
Level 3 [Member] | Monte Carlo Simulation Approach [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Embedded contractual derivative asset	5,800	10,000
Embedded contractual derivative liability	10,100	2,600
Level 3 [Member] | Income Approach [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Assets Held-for-sale, Long Lived, Fair Value Disclosure		50,000
Level 3 [Member] | Western Region Operations [Member] | Income Approach [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Goodwill	$ 558,900	$ 558,900
Assets Held-for-sale [Member] | Level 3 [Member] | Income Approach [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount Rate, range (as a percentage)		12.00%
Assets Held-for-sale [Member] | Level 3 [Member] | Income Approach [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount Rate, range (as a percentage)		12.00%
Assets Held-for-sale [Member] | Level 3 [Member] | Income Approach [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount Rate, range (as a percentage)		12.00%
Embedded contractual derivative asset [Member] | Level 3 [Member] | Monte Carlo Simulation Approach [Member] | Health Net Health Care Expenditures [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Health Care Expenditures, range (as a percentage)	(4.46%)	(0.08%)
Embedded contractual derivative asset [Member] | Level 3 [Member] | Monte Carlo Simulation Approach [Member] | Health Net Health Care Expenditures [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Health Care Expenditures, range (as a percentage)	12.64%	2.74%
Embedded contractual derivative asset [Member] | Level 3 [Member] | Monte Carlo Simulation Approach [Member] | Health Net Health Care Expenditures [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Health Care Expenditures, range (as a percentage)	2.64%	2.02%
Embedded contractual derivative asset [Member] | Level 3 [Member] | Monte Carlo Simulation Approach [Member] | National Health Care Expenditures [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Health Care Expenditures, range (as a percentage)	(0.21%)	3.45%
Embedded contractual derivative asset [Member] | Level 3 [Member] | Monte Carlo Simulation Approach [Member] | National Health Care Expenditures [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Health Care Expenditures, range (as a percentage)	8.59%	4.14%
Embedded contractual derivative asset [Member] | Level 3 [Member] | Monte Carlo Simulation Approach [Member] | National Health Care Expenditures [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Health Care Expenditures, range (as a percentage)	3.83%	3.80%
Embedded contractual derivative liability [Member] | Level 3 [Member] | Monte Carlo Simulation Approach [Member] | Health Net Health Care Expenditures [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Health Care Expenditures, range (as a percentage)	5.97%	0.79%
Embedded contractual derivative liability [Member] | Level 3 [Member] | Monte Carlo Simulation Approach [Member] | Health Net Health Care Expenditures [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Health Care Expenditures, range (as a percentage)	9.48%	10.76%
Embedded contractual derivative liability [Member] | Level 3 [Member] | Monte Carlo Simulation Approach [Member] | Health Net Health Care Expenditures [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Health Care Expenditures, range (as a percentage)	7.49%	5.73%
Embedded contractual derivative liability [Member] | Level 3 [Member] | Monte Carlo Simulation Approach [Member] | National Health Care Expenditures [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Health Care Expenditures, range (as a percentage)	(1.32%)	0.64%
Embedded contractual derivative liability [Member] | Level 3 [Member] | Monte Carlo Simulation Approach [Member] | National Health Care Expenditures [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Health Care Expenditures, range (as a percentage)	8.49%	8.43%
Embedded contractual derivative liability [Member] | Level 3 [Member] | Monte Carlo Simulation Approach [Member] | National Health Care Expenditures [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Health Care Expenditures, range (as a percentage)	3.62%	4.38%
Goodwill [Member] | Level 3 [Member] | Western Region Operations [Member] | Income Approach [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount Rate, range (as a percentage)	7.50%	7.50%
Goodwill [Member] | Level 3 [Member] | Western Region Operations [Member] | Income Approach [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount Rate, range (as a percentage)	7.50%	7.50%
Goodwill [Member] | Level 3 [Member] | Western Region Operations [Member] | Income Approach [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount Rate, range (as a percentage)	7.50%	7.50%