NONCONTROLLING INTEREST PUTS (Details) (Ontario Joint Venture Business Acquisition [Member], USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2013
Ontario Joint Venture Business Acquisition [Member]
Noncontrolling Interest [Line Items]
Value of noncontrolling interest put	$ 5.2
Combined contractual value of noncontrolling interest puts	$ 14.8

Change in additional paid-in capital as a result of the initial difference between the value of the put and the underlying noncontrolling interest being recorded as additional noncontrolling interest and as a reduction to additional paid-in capital.

No definition available.

Name:	lh_ValueOfNoncontrollingInterestPut
Namespace Prefix:	lh_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration