SUPPLEMENTAL CASH FLOW INFORMATION (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Debt Conversion [Line Items]
Noncash conversion of zero-coupon convertible debt	$ 0	$ 2.8
Fair Value of Assets Acquired	16.7us-gaap_FairValueOfAssetsAcquired	3.1us-gaap_FairValueOfAssetsAcquired
Increase (Decrease) in Accrued Liabilities	(1.4)	4.7
Cash paid during period for:
Interest	14.9lh_InterestPaidInCash	18.8lh_InterestPaidInCash
Income taxes, net of refunds	23.1us-gaap_IncomeTaxesPaidNet	8.6us-gaap_IncomeTaxesPaidNet
Restricted Stock Awards And Performance Shares Surrendered	7.8	4.6
Other Significant Noncash Transaction, Value of Consideration Given	$ 1,762.5	$ 0

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Change in accrual for property plant and equipment

+ References

No definition available.

+ Details

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- Definition

The amount of cash paid during the current period for interest owed on money borrowed

+ References

No definition available.

+ Details

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- Definition

Noncash conversion of zero-coupon convertible debt

+ References

No definition available.

+ Details

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- Definition

The value of stock related to restricted stock awards and performance shares forfeited during the period in noncash investing or financing transactions.

+ References

No definition available.

+ Details

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- Definition

The fair value of assets acquired in noncash investing or financing activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

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- Definition

The value of the noncash (or part noncash) consideration given (for example, liability, equity) in a transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of a transaction not resulting in cash receipts or cash payments in the period.

+ References

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