Schedule IV - Reinsurance (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Premiums:
Ceded to other companies, premiums	$ 146	$ 128	$ 276	$ 269
Net amount	$ 7,432	$ 6,800	$ 14,834	$ 13,476