SCHEDULE I-PARENT COMPANY FINANCIAL INFORMATION (Condensed Balance Sheets) (Detail) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 2,343	$ 4,042	$ 3,877	$ 2,571
Investment securities	10,026	9,557
Other current assets	3,564	2,949
Total current assets	16,948	17,402
Property and equipment, net	1,735	1,584
Equity method investment in Kindred at Home	1,047	0
Other long-term assets	1,375	2,166
Total assets	25,413	27,178
Current liabilities:
Book overdraft	171	141
Short-term debt	1,694	150
Total current liabilities	10,077	9,406
Long-term debt	4,375	4,770
Other long-term liabilities	581	237
Total liabilities	15,252	17,336
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $1 par; 10,000,000 shares authorized; none issued	0	0
Common stock, $0.16 2/3 par; 300,000,000 shares authorized; 198,594,841 shares issued at December 31, 2018 and 198,572,458 shares issued at December 31, 2017	33	33
Capital in excess of par value	2,535	2,445
Retained earnings	15,072	13,670
Accumulated other comprehensive (loss) income	(159)	19
Treasury stock, at cost, 63,028,169 shares at December 31, 2018 and 60,893,762 shares at December 31, 2017	(7,320)	(6,325)
Total stockholders’ equity	10,161	9,842	10,685	10,346
Total liabilities and stockholders’ equity	25,413	27,178
Parent Company
Current assets:
Cash and cash equivalents	265	383	$ 1,710	$ 1,389
Investment securities	313	305
Receivable from operating subsidiaries	1,306	1,042
Other current assets	628	245
Total current assets	2,512	1,975
Property and equipment, net	1,209	1,091
Investments in subsidiaries	16,951	16,810
Equity method investment in Kindred at Home	1,047	0
Other long-term assets	359	426
Total assets	22,078	20,302
Current liabilities:
Payable to operating subsidiaries	4,487	4,311
Current portion of notes payable to operating subsidiaries	28	28
Book overdraft	38	41
Short-term debt	1,694	150
Other current liabilities	791	896
Total current liabilities	7,038	5,426
Long-term debt	4,375	4,770
Other long-term liabilities	504	264
Total liabilities	11,917	10,460
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $1 par; 10,000,000 shares authorized; none issued	0	0
Common stock, $0.16 2/3 par; 300,000,000 shares authorized; 198,594,841 shares issued at December 31, 2018 and 198,572,458 shares issued at December 31, 2017	33	33
Capital in excess of par value	2,535	2,445
Retained earnings	15,072	13,670
Accumulated other comprehensive (loss) income	(159)	19
Treasury stock, at cost, 63,028,169 shares at December 31, 2018 and 60,893,762 shares at December 31, 2017	(7,320)	(6,325)
Total stockholders’ equity	10,161	9,842
Total liabilities and stockholders’ equity	$ 22,078	$ 20,302