Medical Costs Payable (Tables)

6 Months Ended

Jun. 30, 2016

Insurance [Abstract]

Schedule of Liability for Unpaid Claims and Claims Adjustment Expense [Table Text Block]

The following table shows the components of the change in medical costs payable for the six months ended June 30:

(in millions)	2017			2016
Medical costs payable, beginning of period	$	16,391		$	14,330
Acquisitions	76			—
Reported medical costs:
Current year	65,208			58,602
Prior years	(580		)	(300		)
Total reported medical costs	64,628			58,302
Medical payments:
Payments for current year	(49,673		)	(43,476		)
Payments for prior years	(13,712		)	(12,524		)
Total medical payments	(63,385		)	(56,000		)
Medical costs payable, end of period	$	17,710		$	16,632