Capital Stock Capital Stock (Narrative) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2013	Sep. 25, 2013
Capital [Abstract]
Autorization date of an increase to the stock repurchase program	Sep. 25, 2013
Increase in stock repurchase program authorization		$ 3,500.0

The amount of an increase authorized by an entity's Board of Directors to a previously authorized stock repurchase program.

No definition available.

Name:	wlp_IncreaseInStockRepurchaseProgramAuthorization
Namespace Prefix:	wlp_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant