Laboratory Corporation of America (LH) 10-Q 10 Nov 14 2014 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information Document	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Nov. 06, 2014
Document Information [Line Items]	'	'
Entity Registrant Name	'LABORATORY CORP OF AMERICA HOLDINGS	'
Entity Central Index Key	'0000920148	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Large Accelerated Filer	'
Document Type	'10-Q	'
Document Period End Date	30-Sep-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q3	'
Amendment Flag	'false	'
Entity Common Stock, Shares Outstanding	'	84.5

CONDENSED_CONSOLIDATED_BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$575.70	$404
Accounts receivable, net of allowance for doubtful accounts of $198.4 and $191.5 at March 31, 2013 and December 31, 2012, respectively	841.6	784.7
Supplies inventories	138.8	136.5
Prepaid expenses and other	126.3	106.9
Deferred Tax Assets, Net of Valuation Allowance, Current	5.4	0
Total current assets	1,687.80	1,432.10
Property, plant and equipment, net	754.7	707.4
Goodwill, net	3,066.40	3,022.80
Intangible assets, net	1,489.40	1,572
Joint venture partnerships and equity method investments	94.7	88.5
Other assets, net	138.8	143.1
Total assets	7,231.80	6,965.90
Current liabilities:	'	'
Accounts payable	286.2	304.5
Accrued expenses and other	365.2	310
Deferred Tax Liabilities, Net, Current	0	9.9
Short-term borrowings and current portion of long-term debt	97.6	111.3
Liabilities, Current	749	735.7
Long-term debt, less current portion	2,917.10	2,889.10
Deferred income taxes and other tax liabilities	552.6	563.9
Other liabilities	223.9	266.5
Total liabilities	4,442.60	4,455.20
Commitments and contingent liabilities	'	'
Noncontrolling interest	18.4	19.4
Shareholders' equity:	'	'
Common stock, 92.8 and 93.5 shares outstanding at March 31, 2013 and December 31, 2012, respectively	10.4	10.5
Additional paid-in capital	0	0
Retained earnings	3,685.60	3,373.50
Less common stock held in treasury	-965.5	-958.9
Accumulated other comprehensive income	40.3	66.2
Total shareholders' equity	2,770.80	2,491.30
Total liabilities and shareholders' equity	$7,231.80	$6,965.90

CONDENSED_CONSOLIDATED_BALANCE1

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parentheticals) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Current Assets:	'	'
Allowance for doubtful accounts	$216.10	$198.30
Shareholders' Equity:	'	'
Common stock, shares outstanding (in shares)	84.9	85.7

CONDENSED_CONSOLIDATED_STATEME

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) (USD $)	3 Months Ended		9 Months Ended
In Millions, except Per Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Income Statement [Abstract]	'	'	'	'
Net sales	$1,551.80	$1,462.20	$4,498.90	$4,371.30
Cost of sales	980.6	914.6	2,842.30	2,674.20
Gross profit	571.2	547.6	1,656.60	1,697.10
Selling, general and administrative expenses	305.7	279	888.5	843.1
Amortization of intangibles and other assets	18.3	20.3	61.3	60.3
Restructuring and other special charges	5.8	3.7	15.4	17.8
Operating income	241.4	244.6	691.4	775.9
Other income (expenses):	'	'	'	'
Interest expense	-25.9	-24.7	-77.4	-72.3
Equity method income, net	3.7	3.6	10.4	12.3
Investment income	0.3	1.8	0.9	2.2
Other, net	-0.5	4.7	13.9	3.3
Earnings before income taxes	219	230	639.2	721.4
Provision for income taxes	81.5	81.3	246.5	272.7
Net earnings	137.5	148.7	392.7	448.7
Less: Net earnings attributable to the noncontrolling interest	-0.3	-0.4	-1.1	-1.2
Net earnings attributable to Laboratory Corporation of America Holdings	$137.20	$148.30	$391.60	$447.50
Basic earnings per common share (in dollars per share)	$1.62	$1.66	$4.61	$4.90
Diluted earnings per common share (in dollars per share)	$1.59	$1.63	$4.53	$4.81

CONDENSED_CONSOLIDATED_STATEME1

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS (Unaudited) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014		Sep. 30, 2013
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]	'	'	'		'
Net earnings	$137.50	$148.70	$392.70		$448.70
Other Comprehensive Earnings, Net of Tax	'	'	'		'
Foreign currency translation adjustments	-48.6	22.4	-49.1		-36.7
Net benefit plan adjustments	'	'	-0.9	[1]	'
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax	-20.7	-2.5	-25.2		-9
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax	-2	0	-18.4		0
Other comprehensive earnings (loss) before tax	-29.9	24.9	-42.3		-27.7
Provision for income tax related to items of comprehensive earnings	-11.7	9.5	-16.4		-10.4
Other comprehensive earnings (loss), net of tax	-18.2	15.4	-25.9		-17.3
Comprehensive earnings	119.3	164.1	366.8		431.4
Less: Net earnings attributable to the noncontrolling interest	-0.3	-0.4	-1.1		-1.2
Comprehensive earnings attributable to Laboratory Corporation of America Holdings	$119	$163.70	$365.70		$430.20
[1]	The amortization of prior service cost is included in the computation of net periodic benefit cost. See NoteB 9 (Pension and Post-retirement Plans) below for additional information regarding the Company's net periodic benefit cost.

CONDENSED_CONSOLIDATED_STATEME2

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Unaudited) (USD $)	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income [Member]
In Millions
BALANCE at Dec. 31, 2012	$2,717.40	$11.30	$0	$3,588.50	($951.80)	$69.40
Net earnings attributable to Laboratory Corporation of America Holdings	447.5	'	'	447.5	'	'
Other comprehensive earnings, net of tax	-17.3	'	'	'	'	-17.3
Issuance of common stock under employee stock plans	148.6	0.2	148.4	'	'	'
Surrender of restricted stock and performance share awards	-7.1	'	'	'	-7.1	'
Conversion of zero-coupon convertible debt	4.7	0	4.7	'	'	'
Stock compensation	28.9	'	28.9	'	'	'
Income tax benefit from stock options exercised	8.4	'	8.4	'	'	'
Purchase of common stock	-765.5	-0.8	-190.4	-574.3	'	'
BALANCE at Sep. 30, 2013	2,565.60	10.7	0	3,461.70	-958.9	52.1
BALANCE at Dec. 31, 2013	2,491.30	10.5	0	3,373.50	-958.9	66.2
Net earnings attributable to Laboratory Corporation of America Holdings	391.6	'	'	391.6	'	'
Other comprehensive earnings, net of tax	-25.9	'	'	'	'	-25.9
Issuance of common stock under employee stock plans	106.2	0	106.2	'	'	'
Surrender of restricted stock and performance share awards	-6.6	'	'	'	-6.6	'
Conversion of zero-coupon convertible debt	3.5	'	'	'	'	'
Stock compensation	35.1	'	35.1	'	'	'
Income tax benefit from stock options exercised	5.5	'	5.5	'	'	'
Purchase of common stock	-229.9	-0.1	-150.3	-79.5	'	'
BALANCE at Sep. 30, 2014	$2,770.80	$10.40	$0	$3,685.60	($965.50)	$40.30

CONDENSED_CONSOLIDATED_STATEME3

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
CASH FLOWS FROM FINANCING ACTIVITIES:	'	'
Proceeds from revolving credit facilities	$0	$412
Payments on zero-coupon subordinated notes	-16.8	-21.3
Payments on long-term debt	0	-350
Noncontrolling interest distributions	-0.9	-0.6
Deferred payments on acquisitions	-5.2	-5.6
Repayments of Long-term Capital Lease Obligations	-0.6	0
Excess tax benefits from stock based compensation	5.5	8.7
Net proceeds from issuance of stock to employees	106.2	148.6
Purchase of common stock	-229.9	-765.5
Payments on revolving credit facilities	0	-40
Net cash provided by (used for) financing activities	-141.8	-613.7
Payments of Debt Issuance Costs	0.1	0
CASH FLOWS FROM OPERATING ACTIVITIES:	'	'
Net earnings	392.7	448.7
Adjustments to reconcile net earnings to net cash provided by operating activities:	'	'
Depreciation and amortization	182	170.3
Stock compensation	35.1	28.9
Loss on sale of assets	-16	-4.3
Accrued interest on zero-coupon subordinated notes	1.5	1.8
Cumulative earnings in excess of distributions from equity method investments	-3.3	-1.7
Deferred income taxes	-3.5	28.3
Change in assets and liabilities (net of effects of acquisitions):	'	'
Increase in accounts receivable (net)	-59.7	-95.5
Increase in inventories	-1.3	-5.6
Decrease in prepaid expenses and other	1.7	-5.3
Decrease in accounts payable	-16.2	25.2
Increase (decrease) in accrued expenses and other	12.3	-20.8
Net cash provided by operating activities	525.3	570
CASH FLOWS FROM INVESTING ACTIVITIES:	'	'
Capital expenditures	-157.2	-142.6
Proceeds from sale of assets	0.9	0.6
Payments for (Proceeds from) Investments	31.7	7.5
Investments in equity affiliates	-12.9	-3.3
Acquisition of businesses, net of cash acquired	-65.3	-109
Net cash used for investing activities	-202.8	-246.8
Effect of exchange rate changes on cash and cash equivalents	-9	-2.2
Net increase (decrease) in cash and cash equivalents	171.7	-292.7
Cash and cash equivalents at beginning of period	404	466.8
Cash and cash equivalents at end of period	$575.70	$174.10

BASIS_OF_FINANCIAL_STATEMENT_P

BASIS OF FINANCIAL STATEMENT PRESENTATION	9 Months Ended
	Sep. 30, 2014
Accounting Policies [Abstract]	'
Basis of Financial Statement Presentation	'
	BASIS OF FINANCIAL STATEMENT PRESENTATION
	The condensed consolidated financial statements include the accounts of Laboratory Corporation of America Holdings (the “Company”) and its majority-owned subsidiaries over which it exercises control. Long-term investments in affiliated companies in which the Company exercises significant influence, but which it does not control, are accounted for using the equity method. Investments in which the Company does not exercise significant influence (generally, when the Company has an investment of less than 20% and no representation on the investee’s board of directors) are accounted for using the cost method. All significant inter-company transactions and accounts have been eliminated. The Company does not have any variable interest entities or special purpose entities whose financial results are not included in the condensed consolidated financial statements.
	The financial statements of the Company’s foreign subsidiaries are measured using the local currency as the functional currency. Assets and liabilities are translated at exchange rates as of the balance sheet date. Revenues and expenses are translated at average monthly exchange rates prevailing during the period. Resulting translation adjustments are included in “Accumulated other comprehensive income.”
	The accompanying condensed consolidated financial statements of the Company are unaudited. In the opinion of management, all adjustments necessary for a fair statement of results of operations, cash flows and financial position have been made. Except as otherwise disclosed, all such adjustments are of a normal recurring nature. Interim results are not necessarily indicative of results for a full year. The year-end condensed consolidated balance sheet data was derived from audited financial statements but does not include all disclosures required by generally accepted accounting principles.
	The financial statements and notes are presented in accordance with the rules and regulations of the Securities and Exchange Commission and do not contain certain information included in the Company’s 2013 Annual Report on Form 10-K. Therefore, the interim statements should be read in conjunction with the consolidated financial statements and notes thereto contained in the Company’s Annual Report.
	New Accounting Pronouncements
	In February 2013, the FASB issued a new accounting standard on joint and several liability arrangements for which the total amount of the obligation is fixed at the reporting date. Under this new standard, obligations resulting from joint and several liability arrangements are to be measured as the sum of: (a) the amount the reporting entity agreed with its co-obligors that it will pay and (b) any additional amount the reporting entity expects to pay on behalf of its co-obligors. This standard, which applies prospectively, became effective for the Company beginning January 1, 2014. The adoption of this standard does not have a material effect on the consolidated financial statements.
	In March 2013, the FASB issued a new accounting standard on foreign currency matters that clarifies the guidance of a parent company's accounting for the cumulative translation adjustment upon derecognition of certain subsidiaries or groups of assets within a foreign entity or of an investment in a foreign entity. Under this new standard, a parent company that ceases to have a controlling financial interest in a foreign subsidiary or group of assets within a foreign entity shall release any related cumulative translation adjustment into net income only if a sale or transfer results in complete or substantially complete liquidation of the foreign entity. This standard, which applies prospectively, became effective for the Company beginning January 1, 2014. The adoption of this standard does not have a material effect on the consolidated financial statements.
	In April 2014, the FASB issued a new accounting standard on discontinued operations that significantly changes criteria for discontinued operations and disclosures for disposals. Under this new standard, to be a discontinued operation, a component or group of components must represent a strategic shift that has (or will have) a major effect on an entity's operations and financial results. Expanded disclosures for discontinued operations include more details about earnings and balance sheet accounts, total operating and investing cash flows, and cash flows resulting from continuing involvement. The guidance is to be applied prospectively to all new disposals of components and new classifications as held for sale beginning in 2015, with early adoption allowed in 2014. The adoption of this standard is not expected to have a material impact on the consolidated financial statements.
	In May 2014, the FASB issued the converged standard on revenue recognition with the objective of providing a single, comprehensive model for all contracts with customers to improve comparability in the financial statements of companies reporting using International Financial Reporting Standards and U.S. Generally Accepted Accounting Principles. The standard contains principles that an entity must apply to determine the measurement of revenue and timing of when it is recognized. The underlying principle is that an entity must recognize revenue to depict the transfer of goods or services to customers at an amount that the entity expects to be entitled to in exchange for those goods or services. An entity can apply the revenue standard retrospectively to each prior reporting period presented (full retrospective method) or retrospectively with the cumulative effect of initially applying the standard recognized at the date of initial application in retained earnings. The revenue standard is effective for the Company beginning January 1, 2017. The Company is currently evaluating the expected impact of the standard.
	In August 2014, the FASB issued a new accounting standard that explicitly requires management to assess an entity's ability to continue as a going concern, and to provide related financial statement footnote disclosures in certain circumstances. Under this standard, in connection with each annual and interim period, management must assess whether there is substantial doubt about an entity's ability to continue as a going concern within one year after the financial statements are issued (or available to be issued when applicable). Management shall consider relevant conditions and events that are known and reasonably knowable at such issuance date. Substantial doubt about an entity's ability to continue as a going concern exists if it is probable that the entity will be unable to meet its obligations as they become due within one year after issuance date. Disclosures will be required if conditions or events give rise to substantial doubt. This standard is effective for the Company for the annual period after December 15, 2016, with early adoption permitted. The adoption of this standard is not expected to have a material impact on the consolidated financial statements.

EARNINGS_PER_SHARE

EARNINGS PER SHARE	9 Months Ended
	Sep. 30, 2014
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	EARNINGS PER SHARE
	Basic earnings per share is computed by dividing net earnings attributable to Laboratory Corporation of America Holdings by the weighted average number of common shares outstanding. Diluted earnings per share is computed by dividing net earnings including the impact of dilutive adjustments by the weighted average number of common shares outstanding plus potentially dilutive shares, as if they had been issued at the earlier of the date of issuance or the beginning of the period presented. Potentially dilutive common shares result primarily from the Company’s outstanding stock options, restricted stock awards, restricted stock units, performance share awards, and shares issuable upon conversion of zero-coupon subordinated notes.
	The following represents a reconciliation of basic earnings per share to diluted earnings per share:
		Three Months Ended September 30,													Nine Months Ended September 30,
		2014								2013					2014					2013
		Income			Shares		Per			Income		Shares	Per		Income		Shares	Per		Income		Shares	Per
							Share						Share					Share					Share
							Amount						Amount					Amount					Amount
	Basic earnings per share:
	Net earnings	$	137.2		84.9		$	1.62		$	148.3	89.2	$	1.66	$	391.6	84.9	$	4.61	$	447.5	91.4	$	4.9
	Dilutive effect of employee stock options and awards	—			1.1					—		1.1			—		1.1			—		1
	Effect of convertible debt	—			0.5					—		0.6			—		0.5			—		0.6
	Diluted earnings per share:
	Net earnings including impact of dilutive adjustments	$	137.2		86.5		$	1.59		$	148.3	90.9	$	1.63	$	391.6	86.5	$	4.53	$	447.5	93	$	4.81
	The following table summarizes the potential common shares not included in the computation of diluted earnings per share because their impact would have been antidilutive:
		Three Months Ended September 30,				Nine Months Ended September 30,
		2014		2013		2014			2013
	Stock options	—		—		—			0.4

RESTRUCTURING_AND_OTHER_SPECIA

RESTRUCTURING AND OTHER SPECIAL CHARGES	9 Months Ended
	Sep. 30, 2014
Restructuring and Related Activities [Abstract]	'
Restructuring and Other Special Charges	'
	RESTRUCTURING AND OTHER SPECIAL CHARGES
	During the first nine months of 2014, the Company recorded net restructuring charges of $15.4. The charges were comprised of $9.8 related to severance and other personnel costs along with $6.7 in costs associated with facility closures and general integration initiatives. These charges were offset by the reversal of previously established reserves of $0.4 in unused severance and $0.7 in unused facility-related costs.
	In addition, during the first nine months of 2014, the Company recorded $10.1 in consulting expenses (recorded in selling, general and administrative expenses) relating to fees incurred as part of its business process improvement initiative as well as one-time CFO transition costs and accrued legal fees for an announced business acquisition.
	During the first nine months of 2013, the Company recorded net restructuring charges of $17.8. The charges were comprised of $11.8 related to severance and other personnel costs along with $8.8 in costs associated with facility closures and general integration initiatives. These charges were offset by the reversal of previously established reserves of $0.7 in unused severance and $2.1 in unused facility-related costs.
	The following represents the Company’s restructuring reserve activities for the period indicated:
		Severance			Lease			Total
		and Other			and Other
		Employee			Facility
		Costs			Costs
	Balance as of December 31, 2013	$	0.8		$	24.9		$	25.7
	Restructuring charges	9.8			6.7			16.5
	Reduction of prior restructuring accruals	(0.4		)	(0.7		)	(1.1		)
	Cash payments and other adjustments	(9.1		)	(7.8		)	(16.9		)
	Balance as of September 30, 2014	$	1.1		$	23.1		$	24.2
	Current							$	9.9
	Non-current							14.3
								$	24.2
		Severance			Lease			Total
		and Other			and Other
		Employee			Facility
		Costs			Costs
	Balance as of December 31, 2013	$	0.8		$	24.9		$	25.7
	Restructuring charges	9.8			6.7			16.5
	Reduction of prior restructuring accruals	(0.4		)	(0.7		)	(1.1		)
	Cash payments and other adjustments	(9.1		)	(7.8		)	(16.9		)
	Balance as of September 30, 2014	$	1.1		$	23.1		$	24.2
	Current							$	9.9
	Non-current							14.3
								$	24.2

GOODWILL_AND_INTANGIBLE_ASSETS

GOODWILL AND INTANGIBLE ASSETS	9 Months Ended
	Sep. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Goodwill and Intangible Assets	'
	GOODWILL AND INTANGIBLE ASSETS
	The changes in the carrying amount of goodwill for the nine-month period ended September 30, 2014 and for the year ended December 31, 2013 are as follows:
		Clinical Diagnostics Laboratory Segment					Other Segment						Total
		September 30,		December 31, 2013			September 30,			December 31, 2013			September 30,			December 31, 2013
		2014					2014						2014
	Balance as of January 1	$	2,960.20	$	2,857.10		$	62.6		$	44.6		$	3,022.80		$	2,901.70
	Goodwill acquired during the period	46.7		107.5			—			19.5			46.7			127
	Adjustments to goodwill	—		(4.4		)	(3.1		)	(1.5		)	(3.1		)	(5.9		)
	Balance at end of period	$	3,006.90	$	2,960.20		$	59.5		$	62.6		$	3,066.40		$	3,022.80
	The components of identifiable intangible assets are as follows:
		September 30, 2014								December 31, 2013
		Gross		Accumulated			Net			Gross			Accumulated			Net
		Carrying		Amortization						Carrying			Amortization
		Amount								Amount
	Customer relationships	$	1,337.90	$	(591.4	)	$	746.5		$	1,327.00		$	(545.1	)	$	781.9
	Patents, licenses and technology	120.7		(93.3		)	27.4			116.2			(85.4		)	30.8
	Non-compete agreements	44.6		(30.1		)	14.5			41.6			(25.3		)	16.3
	Trade names	131.3		(89.4		)	41.9			131.4			(83.0		)	48.4
	Canadian licenses	659.1		—			659.1			694.6			—			694.6
		$	2,293.60	$	(804.2	)	$	1,489.40		$	2,310.80		$	(738.8	)	$	1,572.00
	Amortization of intangible assets for the three and nine month periods ended September 30, 2014 was $18.3 and $61.3, respectively; and $20.3 and $60.3 for the three and nine month periods ended September 30, 2013, respectively. Amortization expense for the net carrying amount of intangible assets is estimated to be $20.1 for the remainder of fiscal 2014, $82.6 in fiscal 2015, $77.3 in fiscal 2016, $70.1 in fiscal 2017, $59.3 in fiscal 2018 and $500.7 thereafter.

DEBT

DEBT	9 Months Ended
	Sep. 30, 2014
Debt Disclosure [Abstract]	'
Debt	'
	DEBT
	Short-term borrowings and the current portion of long-term debt at September 30, 2014 and December 31, 2013 consisted of the following:
		September 30,		December 31, 2013
		2014
	Zero-coupon convertible subordinated notes	$	95.6	$	110.8
	Current portion of capital leases	2		0.5
	Total short-term borrowings and current portion of long-term debt	$	97.6	$	111.3
	Long-term debt at September 30, 2014 and December 31, 2013 consisted of the following:
		September 30,		December 31, 2013
		2014
	5.625% senior notes due 2015	$	250	$	250
	3.125% senior notes due 2016	325		325
	2.20% senior notes due 2017	500		500
	2.50% senior notes due 2018	400		400
	4.625% senior notes due 2020	617		600
	3.75% senior notes due 2022	500		500
	4.00% senior notes due 2023	300		300
	Capital leases	25.1		14.1
	Total long-term debt	$	2,917.10	$	2,889.10
	Senior Notes
	During the third quarter of 2013, the Company entered into two fixed-to-variable interest rate swap agreements for the 4.625% senior notes due 2020 with an aggregate notional amount of $600.0 and variable interest rates based on one-month LIBOR plus 2.298% to hedge against changes in the fair value of a portion of the Company's long term debt.  These derivative financial instruments are accounted for as fair value hedges of the senior notes due 2020.  These interest rate swaps are included in other long term assets and added to the value of the senior notes, with an aggregate fair value of $17.0 at September 30, 2014.
	Zero-Coupon Subordinated Notes
	During the nine months ended September 30, 2014, the Company settled notices to convert $19.4 aggregate principal amount at maturity of its zero-coupon subordinated notes with a conversion value of $25.4. The total cash used for these settlements was $16.8 and the Company also issued 0.1 additional shares of common stock.
	On September 12, 2014, the Company announced that for the period from September 12, 2014 to March 11, 2015, the zero-coupon subordinated notes will accrue contingent cash interest at a rate of no less than 0.125% of the average market price of a zero-coupon subordinated note for the five trading days ended September 9, 2014, in addition to the continued accrual of the original issue discount.
	On October 1, 2014, the Company announced that its zero-coupon subordinated notes may be converted into cash and common stock at the conversion rate of 13.4108 per $1,000.0 principal amount at maturity of the notes, subject to the terms of the zero-coupon subordinated notes and the Indenture, dated as of October 24, 2006 between the Company and The Bank of New York Mellon, as trustee and the conversion agent. In order to exercise the option to convert all or a portion of the zero-coupon subordinated notes, holders are required to validly surrender their zero-coupon subordinated notes at any time during the calendar quarter beginning October 1, 2014, through the close of business on the last business day of the calendar quarter, which is 5:00 p.m., New York City time, on Wednesday, December 31, 2014. If notices of conversion are received, the Company plans to settle the cash portion of the conversion obligation (i.e. the accreted principal amount of the securities to be converted) with cash on hand and/or borrowings under the revolving credit facility (the "Revolving Credit Facility"). The remaining amount, if any, will be settled with shares of common stock.
	Credit Facilities
	On December 21, 2011, the Company entered into a credit agreement (the “Credit Agreement”) providing for a five-year $1,000.0 senior unsecured Revolving Credit Facility with Bank of America, N.A., acting as Administrative Agent, Barclays Capital as Syndication Agent, and a group of financial institutions as lending parties. The balances outstanding on the Company's Revolving Credit Facility at September 30, 2014 and December 31, 2013 were $0.0 and $0.0, respectively. The Revolving Credit Facility bears interest at varying rates based upon a base rate or LIBOR plus (in each case) a percentage based on the Company's debt rating with Standard & Poor's and Moody's Ratings Services. As of September 30, 2014, the effective interest rate on the Revolving Credit Facility was 1.13%.
	The Revolving Credit Facility is available for general corporate purposes, including working capital, capital expenditures, acquisitions, funding of share repurchases and other restricted payments permitted under the Credit Agreement. The Credit Agreement also contains limitations on aggregate subsidiary indebtedness and a debt covenant that requires that the Company maintain on the last day of any period of four consecutive fiscal quarters, in each case taken as one accounting period, a ratio of total debt to consolidated EBITDA (Earnings Before Interest, Taxes, Depreciation, and Amortization) of not more than 3.0 to 1.0. The Company was in compliance with all covenants in the Credit Agreement as of September 30, 2014. As of September 30, 2014, the ratio of total debt to consolidated EBITDA was 2.5 to 1.0.

PREFERRED_STOCK_AND_COMMON_SHA

PREFERRED STOCK AND COMMON SHAREHOLDERS' EQUITY	9 Months Ended
	Sep. 30, 2014
Stockholders' Equity Note [Abstract]	'
Preferred Stock and Common Shareholders' Equity	'
	. PREFERRED STOCK AND COMMON SHAREHOLDERS’ EQUITY
	The Company is authorized to issue up to 265.0 shares of common stock, par value $0.10 per share. The Company’s treasury shares are recorded at aggregate cost. The Company is authorized to issue up to 30.0 shares of preferred stock, par value $0.10 per share. There were no preferred shares outstanding as of September 30, 2014.
	The changes in common shares issued and held in treasury are summarized below:
		Issued			Held in			Outstanding
					Treasury
	Common shares at December 31, 2013	108.1			(22.4	)		85.7
	Common stock issued under employee stock plans	1.6			—			1.6
	Common stock issued upon conversion of zero-coupon subordinated notes	0.1			—			0.1
	Surrender of restricted stock and performance share awards	—			(0.1	)		(0.1	)
	Retirement of common stock	(2.4	)		—			(2.4	)
	Common shares at September 30, 2014	107.4			(22.5	)		84.9
	Share Repurchase Program
	As of December 31, 2013, the Company had outstanding authorization from the Board of Directors to purchase up to $1,058.5 of Company common stock based on settled trades as of that date. During the nine months ended September 30, 2014, the Company purchased 2.4 shares of its common stock at a total cost of $229.9. As of September 30, 2014, the Company had outstanding authorization from the Board of Directors to purchase up to $828.6 of Company common stock based on settled trades as of that date. Following the announcement of the proposed acquisition of Covance, Inc., (see Note 15 Subsequent Events below) the Company suspended its share repurchases and if the acquisition proceeds, the Company does not anticipate continuing share repurchases in the near term.
	Accumulated Other Comprehensive Earnings
	The components of accumulated other comprehensive earnings are as follows:
		Foreign				Net				Unrealized Gains and Losses on Available for Sale Securities			Accumulated
		Currency				Benefit							Other
		Translation				Plan							Comprehensive
		Adjustments				Adjustments							Earnings
	Balance at December 31, 2013	$	123.2			$	(67.1	)		$	10.1		$	66.2
	Other comprehensive earnings before reclassifications	(49.1		)		26.1				1.9			(21.1		)
	Amounts reclassified from accumulated other comprehensive earnings to the Condensed Consolidated Statement of Operations (a) (b)	—				(0.9		)		(20.3		)	(21.2		)
	Tax effect of adjustments	19				(9.7		)		7.1			16.4
	Balance at September 30, 2014	$	93.1			$	(51.6	)		$	(1.2	)	$	40.3
	(a) The amortization of prior service cost is included in the computation of net periodic benefit cost. See Note 9 (Pension and Post-retirement Plans) below for additional information regarding the Company's net periodic benefit cost.
	(b) The gain on sale of available for sale securities is included in Other, net on the Condensed Consolidated Statement of Operations for the three and nine months ended September 30, 2014.

INCOME_TAXES

INCOME TAXES	9 Months Ended
	Sep. 30, 2014
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	INCOME TAXES
	The Company does not recognize a tax benefit, unless the Company concludes that it is more likely than not that the benefit will be sustained on audit by the taxing authority based solely on the technical merits of the associated tax position. If the recognition threshold is met, the Company recognizes a tax benefit measured at the largest amount of the tax benefit that the Company believes is greater than 50% likely to be realized.
	The gross unrecognized income tax benefits were $21.9 and $25.6 at September 30, 2014 and December 31, 2013, respectively. It is anticipated that the amount of the unrecognized income tax benefits will change within the next twelve months; however, these changes are not expected to have a significant impact on the results of operations, cash flows or the financial position of the Company.
	As of September 30, 2014 and December 31, 2013, $21.9 and $25.6, respectively, are the approximate amounts of gross unrecognized income tax benefits that, if recognized, would favorably affect the effective income tax rate in future periods.
	The Company recognizes interest and penalties related to unrecognized income tax benefits in income tax expense. Accrued interest and penalties related to uncertain tax positions totaled $8.8 and $9.3 as of September 30, 2014 and December 31, 2013, respectively.
	The valuation allowance provided as a reserve against certain deferred tax assets is $18.1 and $16.5 as of September 30, 2014 and December 31, 2013, respectively. In the first quarter of 2014, a full valuation allowance was established for the Company's write off of a cost basis investment.
	The Company has substantially concluded all U.S. federal income tax matters for years through 2011. Substantially all material state and local, and foreign income tax matters have been concluded through 2008 and 2001, respectively.
	The Company has various state income tax examinations ongoing throughout the year. In October 2011, Canada Revenue Agency initiated an examination of the Company's Canadian income tax returns for 2010 and 2009. Management believes adequate provisions have been recorded related to all open tax years.

COMMITMENTS_AND_CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	9 Months Ended
	Sep. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	COMMITMENTS AND CONTINGENCIES
	The Company is involved from time to time in various claims and legal actions, including arbitrations, class actions, and other litigation (including those described in more detail below), arising in the ordinary course of business. Some of these actions involve claims that are substantial in amount. These matters include, but are not limited to, intellectual property disputes, professional liability, employee related matters, and inquiries, including subpoenas and other civil investigative demands, from governmental agencies and Medicare or Medicaid payers and managed care payers reviewing billing practices or requesting comment on allegations of billing irregularities that are brought to their attention through billing audits or third parties. The Company receives civil investigative demands or other inquiries from various governmental bodies in the ordinary course of its business. Such inquiries can relate to the Company or other healthcare providers. The Company works cooperatively to respond to appropriate requests for information.
	The Company is also named from time to time in suits brought under the qui tam provisions of the False Claims Act and comparable state laws. These suits typically allege that the Company has made false statements and/or certifications in connection with claims for payment from federal or state health care programs. The suits may remain under seal (hence, unknown to the Company) for some time while the government decides whether to intervene on behalf of the qui tam plaintiff. Such claims are an inevitable part of doing business in the health care field today.
	The Company believes that it is in compliance in all material respects with all statutes, regulations and other requirements applicable to its clinical laboratory operations. The clinical laboratory testing industry is, however, subject to extensive regulation, and the courts have not interpreted many of these statutes and regulations. There can be no assurance, therefore, that the applicable statutes and regulations will not be interpreted or applied by a prosecutorial, regulatory or judicial authority in a manner that would adversely affect the Company. Potential sanctions for violation of these statutes and regulations include significant fines, the loss of various licenses, certificates and authorizations, and/or exclusion from participation in government programs.
	Many of the current claims and legal actions against the Company are at preliminary stages, and many of these cases seek an indeterminate amount of damages. The Company records an aggregate legal reserve, which is determined using actuarial calculations based on historical loss rates and assessment of trends experienced in settlements and defense costs. In accordance with FASB Accounting Standards Codification Topic 450, “Contingencies”, the Company establishes reserves for judicial, regulatory, and arbitration matters outside the aggregate legal reserve if and when those matters present loss contingencies that are both probable and estimable. When loss contingencies are not both probable and estimable, the Company does not establish separate reserves.
	The Company is unable to estimate a range of reasonably probable loss for cases described in more detail below in which damages either have not been specified or, in the Company's judgment, are unsupported and/or exaggerated and (i) the proceedings are in early stages; (ii) there is uncertainty as to the outcome of pending appeals or motions; (iii) there are significant factual issues to be resolved; and/or (iv) there are novel legal issues to be presented. For these cases, although the Company does not believe, based on currently available information, that the outcomes will have a material adverse effect on the Company's financial condition, the outcomes could be material to the Company's operating results for any particular period, depending, in part, upon the operating results for such period.
	As previously reported, the Company reached a settlement in the previously disclosed lawsuit, California ex rel. Hunter Laboratories, LLC et al. v. Quest Diagnostics Incorporated, et al. (“Hunter Labs Settlement Agreement”), to avoid the uncertainty and costs associated with prolonged litigation. Pursuant to the executed settlement agreement, the Company recorded a litigation settlement expense of $34.5 in the second quarter of 2011 (net of a previously recorded reserve of $15.0) and paid the settlement amount of $49.5 in the third quarter of 2011. The Company also agreed to certain reporting obligations regarding its pricing for a limited time period and, at the option of the Company in lieu of such reporting obligations, to provide Medi-Cal with a discount from Medi-Cal's otherwise applicable maximum reimbursement rate from November 1, 2011, through October 31, 2012. In June of 2012, the California legislature enacted Assembly Bill No. 1494, Section 9 of which directs the Department of Health Care Services ("DHCS") to establish new reimbursement rates for Medi-Cal clinical laboratory services that will be based on payments made to California clinical laboratories for similar services by other third-party payers. With stakeholder input, DHCS established data elements and a format for laboratories to report payment data from comparable third-party payers. After reviewing the submitted data, DHCS will propose new reimbursement rates and solicit stakeholder input before their implementation. The bill provides that until the new rates are set through this process, Medi-Cal payments for clinical laboratory services will be reduced (in addition to a 10% payment reduction imposed by statute in 2011) by “up to 10 percent” for tests with dates of service on or after July 1, 2012, with a cap on payments set at 80% of the lowest maximum allowance established under the federal Medicare program. Under the terms of the Hunter Labs Settlement Agreement, the enactment of this new California legislation terminated the Company's reporting obligations (or obligation to provide a discount in lieu of reporting) under that agreement.  On March 28, 2014, Assembly Bill No. 1124 extended the implementation deadline of new regulations until June 30, 2016. Taken together, these changes are not expected to have a material impact on the Company's consolidated revenues or results of operations.
	As previously reported, the Company responded to an October 2007 subpoena from the United States Department of Health & Human Services Office of Inspector General's regional office in New York. On August 17, 2011, the Southern District of New York unsealed a False Claims Act lawsuit, United States of America ex rel. NPT Associates v. Laboratory Corporation of America Holdings, which alleges that the Company offered UnitedHealthcare kickbacks in the form of discounts in return for Medicare business. The Plaintiff's third amended complaint further alleges that the Company's billing practices violated the false claims acts of fourteen states and the District of Columbia. The lawsuit seeks actual and treble damages and civil penalties for each alleged false claim, as well as recovery of costs, attorney's fees, and legal expenses. Neither the United States government nor any state government has intervened in the lawsuit. The Company's Motion to Dismiss was granted in October 2014. The Company intends to vigorously defend the lawsuit should it proceed further.
	In addition, the Company has received various other subpoenas since 2007 related to Medicaid billing. In February 2009, the Company received a subpoena from the Commonwealth of Virginia Office of the Attorney General requesting documents related to its billing to Virginia Medicaid. In April of 2013, the Commonwealth of Virginia Office of the Attorney General closed its investigation. In October 2009, the Company received a subpoena from the State of Michigan Department of Attorney General seeking documents related to its billing to Michigan Medicaid. In June 2010, the Company received a subpoena from the State of Florida Office of the Attorney General requesting documents related to its billing to Florida Medicaid. In October 2013, the Company received a civil investigative demand from the State of Texas Office of the Attorney General requesting documents related to its billing to Texas Medicaid. The Company is cooperating with these requests.
	On November 4, 2013, the State of Florida through the Office of the Attorney General filed an Intervention Complaint in a False Claims Act lawsuit, State of Florida ex rel. Hunter Laboratories, LLC and Chris Riedel v. Quest Diagnostics Incorporated, et al. in the Circuit Court for the Second Judicial Circuit for Leon County. The complaint, originally filed by a competitor laboratory, alleges that the Company overcharged Florida’s Medicaid program. The lawsuit seeks actual and treble damages and civil penalties for each alleged false claim, as well as recovery of costs, attorney’s fees, and legal expenses. On January 3, 2014, the Company filed a Petition for the Administrative Determination of the Invalidity of an Existing Rule against the Agency for Health Care Administration (“AHCA”). The Petition sought the invalidity of Rule 59G-5.110(2) of the Florida Administrative Code, which was relied upon by the Attorney General in its Intervention Complaint. On March 28, 2014, an Administrative Law Judge for the State of Florida Division of Administrative Hearings issued an order finding that Rule 59G-5.110(2) of the Florida Administrative Code was invalid. In the interim, the Attorney General filed a First Amended Intervention Complaint on January 30, 2014, which seeks actual and treble damages and civil penalties for alleged false claims, as well as recovery of costs, attorney's fees, and legal expenses, for allegedly overcharging Florida's Medicaid program. The Company will vigorously defend the lawsuit.
	On May 2, 2013, the Company was served with a False Claims Act lawsuit, State of Georgia ex rel. Hunter Laboratories, LLC and Chris Riedel v. Quest Diagnostics Incorporated, et al., filed in the State Court of Fulton County, Georgia. The lawsuit, filed by a competitor laboratory, alleges that the Company overcharged Georgia's Medicaid program. The case was removed to the United States District Court for the Northern District of Georgia. The lawsuit seeks actual and treble damages and civil penalties for each alleged false claim, as well as recovery of costs, attorney's fees, and legal expenses. The government filed a notice declining to intervene in the case. On March 14, 2014, the Company's Motion to Dismiss was granted. The Plaintiffs have filed a motion seeking leave to replead their complaint. The Company will vigorously defend the lawsuit.
	On August 19, 2013, the Company was served with a False Claims Act lawsuit, Commonwealth of Virginia ex rel. Hunter Laboratories, LLC and Chris Riedel v. Quest Diagnostics Incorporated, et al., filed in the Circuit Court of Fairfax County, Virginia. The lawsuit, filed by a competitor laboratory, alleges that the Company overcharged Virginia’s Medicaid program. The case was removed to the United States District Court for the Eastern District of Virginia. The lawsuit seeks actual and treble damages and civil penalties for each alleged false claim, as well as recovery of costs, attorney's fees, and legal expenses. The government filed a notice declining to intervene in the case. The Company's Motion to Dismiss was granted and the Plaintiffs were granted the right to replead their complaint. An amended complaint was filed and the Company's Motion to Dismiss was granted on March 18, 2014. The Plaintiffs filed a notice of appeal. The Company will vigorously defend the lawsuit on appeal.
	In October 2011, a putative stockholder of the Company made a letter demand through his counsel for inspection of documents related to policies and procedures concerning the Company's Board of Directors' oversight and monitoring of the Company's billing and claim submission process. The letter also sought documents prepared for or by the Board regarding allegations from the California ex rel. Hunter Laboratories, LLC et al. v. Quest Diagnostics Incorporated, et al., lawsuit and documents reviewed and relied upon by the Board in connection with the settlement of that lawsuit. The Company responded to the request pursuant to Delaware law.
	On November 18, 2011, the Company received a letter from United States Senators Baucus and Grassley requesting information regarding the Company's relationships with its largest managed care customers. The letter requests information about the Company's contracts and financial data regarding its managed care customers. Company representatives met with Senate Finance Committee staff after receiving the request and subsequently produced documents in response. The Company continues to cooperate with the request for information.
	On February 27, 2012, the Company was served with a False Claims Act lawsuit, United States ex rel. Margaret Brown v. Laboratory Corporation of America Holdings and Tri-State Clinical Laboratory Services, LLC, filed in the United States District Court for the Southern District of Ohio, Western Division. The lawsuit alleges that the Defendants submitted false claims for payment for laboratory testing services performed as a result of financial relationships that violated the federal Stark and anti-kickback laws. The Company owned 50% of Tri-State Clinical Laboratory Services, LLC, which was dissolved in June of 2011 pursuant to a voluntary petition under Chapter 7 of Title 11 of the United States Code. The lawsuit seeks actual and treble damages and civil penalties for each alleged false claim, as well as recovery of costs, attorney's fees, and legal expenses. The United States government has not intervened in the lawsuit. The Company will vigorously defend the lawsuit.
	On June 7, 2012, the Company was served with a putative class action lawsuit, Yvonne Jansky v. Laboratory Corporation of America, et al., filed in the Superior Court of the State of California, County of San Francisco. The lawsuit alleges that the Defendants committed unlawful and unfair business practices, and violated various other state laws by changing screening codes to diagnostic codes on laboratory test orders, thereby resulting in customers being responsible for co-payments and other debts. The lawsuit seeks injunctive relief, actual and punitive damages, as well as recovery of attorney's fees, and legal expenses. The Company will vigorously defend the lawsuit.
	On June 7, 2012, the Company was served with a putative class action lawsuit, Ann Baker Pepe v. Genzyme Corporation and Laboratory Corporation of America Holdings, filed in the United States District Court for the District of Massachusetts. The lawsuit alleges that the Defendants failed to preserve DNA samples allegedly entrusted to the Defendants and thereby breached a written agreement with Plaintiff and violated state laws. The lawsuit seeks injunctive relief, actual, double and treble damages, as well as recovery of attorney's fees and legal expenses. The Company will vigorously defend the lawsuit.
	On August 24, 2012, the Company was served with a putative class action lawsuit, Sandusky Wellness Center, LLC, et al. v. MEDTOX Scientific, Inc., et al., filed in the United States District Court for the District of Minnesota. The complaint alleges that on or about February 21, 2012, the Defendants violated the federal Telephone Consumer Protection Act ("TCPA") by sending unsolicited facsimiles to Plaintiff and more than 39 other recipients without the recipients' prior express permission or invitation. The lawsuit seeks the greater of actual damages or the sum of $0.0005 for each violation, subject to trebling under TCPA, and injunctive relief. In September 2014, Plaintiff's Motion for class certification was denied. The Company will continue to vigorously defend the remaining individual claim in the lawsuit.
	The Company was a defendant in two separate putative class action lawsuits, Christine Bohlander v. Laboratory Corporation of America, et al., and Jemuel Andres, et al. v. Laboratory Corporation of America Holdings, et al., related to overtime pay. After the filing of the two lawsuits on July 8, 2013, the Bohlander lawsuit was consolidated into the Andres lawsuit, and the consolidated lawsuit is now pending in the Superior Court of California for the County of Los Angeles. In the consolidated lawsuit, the Plaintiffs allege on behalf of similarly situated phlebotomists and couriers that the Company failed to pay overtime, failed to provide meal and rest breaks, and committed other violations of the California Labor Code. On March 24, 2014, the Court granted the Company's Motion to Dismiss due to technical deficiencies in the pleading of the Plaintiffs' claims, but granted Plaintiffs leave to amend to cure the defects. Plaintiffs have subsequently filed an amended complaint. The complaint seeks monetary damages, civil penalties, costs, injunctive relief, and attorney's fees. The Company will vigorously defend the lawsuit.
	The Company is also a defendant in two additional putative class action lawsuits alleging similar claims to the Bohlander/Andres consolidated lawsuit. The lawsuit Rachel Rabanes v. California Laboratory Sciences, LLC, et al., was filed in April 2014 in the Superior Court of California for the County of Los Angeles, and the lawsuit Rita Varsam v. Laboratory Corporation of America DBA LabCorp, was filed in June 2014 in the Superior Court of California for the County of San Diego. In these lawsuits, the Plaintiffs allege on behalf of similarly situated employees that the Company failed to pay overtime, failed to provide meal and rest breaks, and committed other violations of the California Labor Code. The complaints seek monetary damages, civil penalties, costs, injunctive relief, and attorney's fees. The Company will vigorously defend these lawsuits.
	On December 17, 2010, the Company was served with a lawsuit, Oliver Wuth, et al. v. Laboratory Corporation of America, et al., filed in the State Superior Court of King County, Washington. The lawsuit alleges that the Company was negligent in the handling of a prenatal genetic test order that allegedly resulted in the parents being given incorrect information. The matter was tried to a jury beginning on October 21, 2013. On December 10, 2013, the jury returned a verdict in in Plaintiffs’ favor in the amount of $50.0, with 50% of liability apportioned to the Company and 50% of liability apportioned to co-Defendant Valley Medical Center. The Company filed post-judgment motions for a new trial, which were denied, and is vigorously pursuing an appeal of the judgment on multiple grounds. The Company carries self-insurance reserves and excess liability insurance sufficient to cover the potential liability in this case.
	On July 3, 2012, the Company was served with a lawsuit, John Wisekal, as Personal Representative of the Estate of Darien Wisekal v. Laboratory Corporation of America Holdings and Glenda C. Mixon, filed in the Circuit Court of the Fifteenth Judicial Circuit in and for Palm Beach County, Florida. The lawsuit alleges that the Company misread a Pap test. The case was removed to the United States District Court for the Southern District of Florida. The matter was tried to a jury beginning on April 1, 2014. On April 17, 2014, the jury returned a verdict in Plaintiff’s favor in the amount of $20.8, with non-economic damages reduced by 25% to account for the Plaintiff's negligence, for a final verdict of $15.8. The Company filed post-trial motions. On July 28, 2014, the Court granted the Company’s motion for remittitur and reduced the jury’s non-economic damages award to $5.0, reduced by 25.0% for the Plaintiff’s negligence. Accordingly, the total judgment is $4.4. The Plaintiff opposed the remitted amount and therefore, the Court has ordered a new trial on the issue of damages only.
	On June 17, 2014, the Company was served with a putative class action lawsuit, Michael Dickerson v. Laboratory Corporation of America, Inc. filed in the United States District Court for the Middle District of Florida. The complaint alleged that the Company violated the federal Telephone Consumer Protection Act (“TCPA”) by placing non-emergency telephone calls to cellular telephones without the recipients’ prior consent or permission. The lawsuit sought the greater of actual damages or the sum of $0.0005 for each violation, subject to trebling under TCPA, and injunctive relief. The lawsuit was dismissed with prejudice in October 2014.
	On July 9, 2014, the Company was served with a putative class action lawsuit, Christopher W. Legg, et al. v. Laboratory Corporation of America, filed in the United States District Court for the Southern District of Florida. The complaint alleges that the Company violated the Fair and Accurate Credit Transactions Act (“FACTA”) by allegedly providing credit card expiration date information on an electronically printed credit card receipt. The lawsuit seeks statutory and punitive damages, injunctive relief, and attorney’s fees. The Company will vigorously defend the lawsuit.
	In October 2014, the Company became aware of, but has not yet been served with, a False Claims Act lawsuit, United States of America and State of California ex rel. Elisa Martinez v. Quest Diagnostics Incorporated, et al., filed in the United States District Court for the Eastern District of California. The lawsuit alleges that the Company submitted false claims to the United States and the State of California for duplicative lab tests. The lawsuit seeks actual and treble damages and civil penalties for each alleged claim, as well as recovery of costs, attorney’s fees, and legal expenses. Neither the United States government nor the State of California has intervened in the lawsuit. The Company intends to vigorously defend the lawsuit in the event that it is served upon the Company.
	In September 2014, the Company and LipoScience, Inc. (“LipoScience”) announced that they had entered into a definitive agreement and plan of merger under which the Company will acquire all of the outstanding shares of LipoScience in a cash tender offer for $5.25 per share for a total purchase price to stockholders and option holders of approximately $85.0. The tender offer and the merger are subject to customary closing conditions set forth in the agreement and plan of merger. In October 2014, the Company was named in two lawsuits filed by putative classes of shareholders of LipoScience, Carren Overby v. LipoScience, Inc., et al, filed in North Carolina state court, and Gautum Patel v. LipoScience, Inc., et al., filed in Delaware state court. The lawsuits name both LipoScience and the Company as defendants and allege breaches of fiduciary duty and/or other violations of state law arising out of the proposed acquisition.
	Under the Company's present insurance programs, coverage is obtained for catastrophic exposure as well as those risks required to be insured by law or contract. The Company is responsible for the uninsured portion of losses related primarily to general, professional and vehicle liability, certain medical costs and workers' compensation. The self-insured retentions are on a per occurrence basis without any aggregate annual limit. Provisions for losses expected under these programs are recorded based upon the Company's estimates of the aggregated liability of claims incurred. As of September 30, 2014, the Company had provided letters of credit aggregating approximately $42.5, primarily in connection with certain insurance programs. The Company's availability under its Revolving Credit Facility is reduced by the amount of these letters of credit.

PENSION_AND_POSTRETIREMENT_PLA

PENSION AND POSTRETIREMENT PLANS	9 Months Ended
	Sep. 30, 2014
Postemployment Benefits [Abstract]	'
Pension And Postretirement Plans	'
	PENSION AND POSTRETIREMENT PLANS
	The Company’s defined contribution retirement plan (the “401K Plan”) covers substantially all employees. All employees eligible for the 401K Plan receive a minimum 3% non-elective contribution concurrent with each payroll period. The 401K Plan also permits discretionary contributions by the Company of up to 1% and up to 3% of pay for eligible employees based on years of service with the Company. The cost of this plan was $12.6 and $12.2 for the three months ended September 30, 2014 and 2013, respectively, and $38.8 and $37.3 for the nine months ended September 30, 2014 and 2013, respectively.
	The Company also maintains a frozen defined benefit retirement plan (the “Company Plan”), that as of December 31, 2009, covered substantially all employees. The benefits to be paid under the Company Plan are based on years of credited service through December 31, 2009 and ongoing interest credits. Effective January 1, 2010, the Company Plan was closed to new participants. The Company’s policy is to fund the Company Plan with at least the minimum amount required by applicable regulations.
	The Company maintains a second unfunded, non-contributory, non-qualified defined benefit retirement plan (the “PEP”), that as of December 31, 2009, covered substantially all of its senior management group. The PEP supplements the Company Plan and was closed to new participants effective January 1, 2010.
	The effect on operations for the Company Plan and the PEP is summarized as follows:
		Three Months Ended September 30,						Nine Months Ended September 30,
		2014			2013			2014			2013
	Service cost for administrative expenses	$	0.8		$	0.7		$	2.5		$	1.9
	Interest cost on benefit obligation	4.2			3.7			12.3			11.1
	Expected return on plan assets	(4.6		)	(4.3		)	(13.6		)	(12.9		)
	Net amortization and deferral	1.6			2.3			5			8.3
	Defined benefit plan costs	$	2		$	2.4		$	6.2		$	8.4
	During the nine months ended September 30, 2014, the Company contributed $10.1 to the Company Plan.
	The Company has assumed obligations under a subsidiary’s post-retirement medical plan. Coverage under this plan is restricted to a limited number of existing employees of the subsidiary. This plan is unfunded and the Company’s policy is to fund benefits as claims are incurred. The effect on operations of the post-retirement medical plan is shown in the following table:
		Three Months Ended September 30,						Nine Months Ended September 30,
		2014			2013			2014			2013
	Service cost for benefits earned	$	0.1		$	0.1		$	0.2		$	0.3
	Interest cost on benefit obligation	0.4			0.6			1.3			1.9
	Net amortization and deferral	(2.0		)	0.2			(5.9		)	0.7
	Post-retirement medical plan (benefit) costs	$	(1.5	)	$	0.9		$	(4.4	)	$	2.9
	In the first quarter of 2014, the Company made certain administrative changes to the Plan which resulted in an expected reduction in future post-retirement medical benefits. The resulting reduction to the post-retirement medical liability was inadvertently not recorded until the third quarter of 2014. As a result, an out of period adjustment of approximately $11.7 (after tax) was recorded to reduce the post-retirement medical liability and increase other comprehensive income. The Company concluded that the impact was not material to the current or prior periods.

FAIR_VALUE_MEASUREMENTS

FAIR VALUE MEASUREMENTS	9 Months Ended
	Sep. 30, 2014
Fair Value Disclosures [Abstract]	'
Fair Value Measurements	'
	FAIR VALUE MEASUREMENTS
	The Company’s population of financial assets and liabilities subject to fair value measurements as of September 30, 2014 and December 31, 2013 is as follows:
				Fair Value Measurements as of
		Fair Value		September 30, 2014
		as of		Using Fair Value Hierarchy
		September 30, 2014		Level 1		Level 2		Level 3
	Noncontrolling interest put	$	18.4	$	—	$	19.3	$	—
	Interest rate swap	17		—		17		—
	Cash surrender value of life insurance policies	40.8		—		40.8		—
	Deferred compensation liability	41.3		—		41.3		—
	Investment in equity securities	1		1		—		—
				Fair Value Measurements as of
		Fair Value		December 31, 2013
		as of		Using Fair Value Hierarchy
		December 31, 2013		Level 1		Level 2		Level 3
	Noncontrolling interest put	$	19.4	$	—	$	19.4	$	—
	Interest rate swap	—		—		—		—
	Cash surrender value of life insurance policies	35.1		—		35.1		—
	Deferred compensation liability	36.3		—		36.3		—
	Investment in equity securities	26.3		26.3		—		—
	The Company has a noncontrolling interest put related to its Ontario subsidiary that has been classified as mezzanine equity in the Company’s condensed consolidated balance sheet. The noncontrolling interest put is valued at its contractually determined value, which approximates fair value.
	The Company offers certain employees the opportunity to participate in a deferred compensation plan (“DCP”). A participant's deferrals are allocated by the participant to one or more of 16 measurement funds, which are indexed to externally managed funds. From time to time, to offset the cost of the growth in the participant's investment accounts, the Company purchases life insurance policies, with the Company named as beneficiary of the policies. Changes in the cash surrender value of these policies are based upon earnings and changes in the value of the underlying investments, which are typically invested in a manner similar to the participants' allocations. Changes in the fair value of the DCP obligation are derived using quoted prices in active markets based on the market price per unit multiplied by the number of units. The cash surrender value and the DCP obligations are classified within Level 2 because their inputs are derived principally from observable market data by correlation to the hypothetical investments.
	The carrying amounts of cash and cash equivalents, accounts receivable, income taxes receivable, and accounts payable are considered to be representative of their respective fair values due to their short-term nature. The fair market value of the zero-coupon subordinated notes, based on market pricing, was approximately $152.3 and $155.5 as of September 30, 2014 and December 31, 2013, respectively. The fair market value of all of the senior notes, based on market pricing, was approximately $2,956.8 and $2,907.8 as of September 30, 2014 and December 31, 2013, respectively. The Company's note and debt instruments are classified as Level 2 instruments, as the fair market values of these instruments are determined using other observable inputs. The Company's investment in an equity security of $1.0 is considered a Level 1 instrument, as the fair market value of this instrument is determined using observable inputs.

DERIVATIVE_INSTRUMENTS_AND_HED

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES	9 Months Ended
	Sep. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Derivative Instruments And Hedging Activities	'
	DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES
	The Company addresses its exposure to market risks, principally the market risk associated with changes in interest rates, through a controlled program of risk management that includes, from time to time, the use of derivative financial instruments such as interest rate swap agreements (see Interest Rate Swap section below). Although the Company’s zero-coupon subordinated notes contain features that are considered to be embedded derivative instruments (see Embedded Derivatives Related to the Zero-Coupon Subordinated Notes section below), the Company does not hold or issue derivative financial instruments for trading purposes. The Company does not believe that its exposure to market risk is material to the Company’s financial position or results of operations.
	Interest Rate Swap
	During the third quarter of 2013, the Company entered into two fixed-to-variable interest rate swap agreements for the 4.625% senior notes due 2020 with an aggregate notional amount of $600.0 and variable interest rates based on one-month LIBOR plus 2.298% to hedge against changes in the fair value of a portion of the Company's long term debt.  These derivative financial instruments are accounted for as fair value hedges of the senior notes due 2020.  These interest rate swaps are included in other long term assets and added to the value of the senior notes, with an aggregate fair value of $17.0 and $0.0 at September 30, 2014 and December 31, 2013, respectively. As the specific terms and notional amounts of the derivative financial instruments match those of the fixed-rate debt being hedged, the derivative instruments are assumed to be perfectly effective hedges and accordingly, there is no impact to the Company's consolidated statements of operations.
	Embedded Derivatives Related to the Zero-Coupon Subordinated Notes
	The Company’s zero-coupon subordinated notes contain the following two features that are considered to be embedded derivative instruments under authoritative guidance in connection with accounting for derivative instruments and hedging activities:
	1)	The Company will pay contingent cash interest on the zero-coupon subordinated notes after September 11, 2006, if the average market price of the notes equals 120% or more of the sum of the issue price, accrued original issue discount and contingent additional principal, if any, for a specified measurement period.
	2)	Holders may surrender zero-coupon subordinated notes for conversion during any period in which the rating assigned to the zero-coupon subordinated notes by Standard & Poor’s Ratings Services is BB- or lower.
	The Company believes these embedded derivatives had no fair value at September 30, 2014 and December 31, 2013. These embedded derivatives also had no impact on the condensed consolidated statements of operations for the nine months ended September 30, 2014 and 2013.

SUPPLEMENTAL_CASH_FLOW_INFORMA

SUPPLEMENTAL CASH FLOW INFORMATION	9 Months Ended
	Sep. 30, 2014
Supplemental Cash Flow Information [Abstract]	'
Supplemental Cash Flow Information	'
	SUPPLEMENTAL CASH FLOW INFORMATION
		Nine Months Ended September 30,
		2014			2013
	Supplemental schedule of cash flow information:
	Cash paid during period for:
	Interest	$	74.7		$	65.4
	Income taxes, net of refunds	211.1			228.1
	Disclosure of non-cash financing and investing activities:
	Surrender of restricted stock awards and performance awards	$	6.6		$	7.1
	Conversion of zero-coupon convertible debt	8.6			10.3
	Assets acquired under capital leases	13.1			9.8
	Increase (decrease) accrued property, plant and equipment	(3.3		)	1.8

BUSINESS_ACQUISITIONS

BUSINESS ACQUISITIONS	9 Months Ended
	Sep. 30, 2014
Business Acquisitions [Abstract]	'
Business Combination Disclosure [Text Block]	'
		BUSINESS ACQUISITIONS
	During the nine months ended September 30, 2014, the Company acquired various laboratories and related assets for approximately $65.3 in cash (net of cash acquired). The purchase consideration for these acquisitions has been allocated to the estimated fair market value of the net assets acquired, including approximately $15.6 in identifiable intangible assets (primarily customer relationships and non-compete agreements) and a residual amount of goodwill of approximately $46.7. These acquisitions were made primarily to extend the Company's geographic reach in important market areas and/or enhance the Company's scientific differentiation and esoteric testing capabilities. For information regarding the Company's pending acquisition of Covance, Inc., see Note 15 (Subsequent Events) below.

BUSINESS_SEGMENT_INFORMATION_B

BUSINESS SEGMENT INFORMATION Business Segment information (Notes)	9 Months Ended
	Sep. 30, 2014
Segment Reporting Information [Line Items]	'
Segment Reporting Disclosure [Text Block]	'
	BUSINESS SEGMENT INFORMATION
	The following table is a summary of segment information for the three and nine months ended September 30, 2014 and 2013. Segment asset information is not presented because it is not used by the chief operating decision maker at the operating segment level. Operating earnings (loss) of each segment represents net revenues less directly identifiable expenses to arrive at operating income for the segment. General management and administrative corporate expenses are included in general corporate expenses below. The accounting policies of the segments are the same as those of the Company as set forth in Note 1 to the Consolidated Financial Statements contained in the Company's Annual Report on Form 10-K for the year ended December 31, 2013 and Note 1 (Basis of Financial Statement Presentation) above to the interim consolidated financial statements.
	Laboratory tests and procedures are used generally by hospitals, physicians and other health care providers and commercial clients to assist in the diagnosis, evaluation, detection, therapy selection, monitoring and treatment of diseases and other medical conditions through the examination of substances in the blood, tissues and other specimens. The Clinical diagnostics laboratory
	segment includes financial information related to the broad range of testing services that are reported primarily through the Company's U.S. business operations. The Other segment includes the portion of the Company's non-U.S. clinical diagnostic laboratory operations in Ontario, Canada, which are reviewed separately by corporate management for the purposes of allocation of resources.
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
		2014			2013			2014			2013
	Net revenues:
	Clinical diagnostics laboratory	$	1,468.90		$	1,377.80		$	4,250.50		$	4,113.40
	Other	82.9			84.4			248.4			257.9
	Total net revenues	1,551.80			1,462.20			4,498.90			4,371.30
	Operating earnings (loss):
	Clinical diagnostics laboratory	375.8			359.5			1,082.50			1,113.80
	Other	21.2			24			64.6			71.7
	General corporate expenses	(155.6		)	(138.9		)	(455.7		)	(409.6		)
	Total operating income	241.4			244.6			691.4			775.9
	Other income (expense), net	(22.4		)	(14.6		)	(52.2		)	(54.5		)
	Earnings before income taxes	219			230			639.2			721.4
	Provision for income taxes	81.5			81.3			246.5			272.7
	Net earnings	137.5			148.7			392.7			448.7
	Less income attributable to noncontrolling interests	(0.3		)	(0.4		)	(1.1		)	(1.2		)
	Net income attributable to Laboratory Corporation of America Holdings	$	137.2		$	148.3		$	391.6		$	447.5

EARNINGS_PER_SHARE_Tables

EARNINGS PER SHARE (Tables)	9 Months Ended
	Sep. 30, 2014
Earnings Per Share [Abstract]	'
Reconciliation of Basic earnings per Share to Diluted Earnings per Share	'
	The following represents a reconciliation of basic earnings per share to diluted earnings per share:
		Three Months Ended September 30,													Nine Months Ended September 30,
		2014								2013					2014					2013
		Income			Shares		Per			Income		Shares	Per		Income		Shares	Per		Income		Shares	Per
							Share						Share					Share					Share
							Amount						Amount					Amount					Amount
	Basic earnings per share:
	Net earnings	$	137.2		84.9		$	1.62		$	148.3	89.2	$	1.66	$	391.6	84.9	$	4.61	$	447.5	91.4	$	4.9
	Dilutive effect of employee stock options and awards	—			1.1					—		1.1			—		1.1			—		1
	Effect of convertible debt	—			0.5					—		0.6			—		0.5			—		0.6
	Diluted earnings per share:
	Net earnings including impact of dilutive adjustments	$	137.2		86.5		$	1.59		$	148.3	90.9	$	1.63	$	391.6	86.5	$	4.53	$	447.5	93	$	4.81
Potential common shares not included in computation of diluted earnings per share	'
	The following table summarizes the potential common shares not included in the computation of diluted earnings per share because their impact would have been antidilutive:
		Three Months Ended September 30,				Nine Months Ended September 30,
		2014		2013		2014			2013
	Stock options	—		—		—			0.4

RESTRUCTURING_AND_OTHER_SPECIA1

RESTRUCTURING AND OTHER SPECIAL CHARGES Restructuring and Other Special Charges Detail (Tables)	9 Months Ended
	Sep. 30, 2014
Restructuring Cost and Reserve [Line Items]	'
Restructuring and Related Costs [Table Text Block]	'
	RESTRUCTURING AND OTHER SPECIAL CHARGES
	During the first nine months of 2014, the Company recorded net restructuring charges of $15.4. The charges were comprised of $9.8 related to severance and other personnel costs along with $6.7 in costs associated with facility closures and general integration initiatives. These charges were offset by the reversal of previously established reserves of $0.4 in unused severance and $0.7 in unused facility-related costs.
	In addition, during the first nine months of 2014, the Company recorded $10.1 in consulting expenses (recorded in selling, general and administrative expenses) relating to fees incurred as part of its business process improvement initiative as well as one-time CFO transition costs and accrued legal fees for an announced business acquisition.
	During the first nine months of 2013, the Company recorded net restructuring charges of $17.8. The charges were comprised of $11.8 related to severance and other personnel costs along with $8.8 in costs associated with facility closures and general integration initiatives. These charges were offset by the reversal of previously established reserves of $0.7 in unused severance and $2.1 in unused facility-related costs.
	The following represents the Company’s restructuring reserve activities for the period indicated:
		Severance			Lease			Total
		and Other			and Other
		Employee			Facility
		Costs			Costs
	Balance as of December 31, 2013	$	0.8		$	24.9		$	25.7
	Restructuring charges	9.8			6.7			16.5
	Reduction of prior restructuring accruals	(0.4		)	(0.7		)	(1.1		)
	Cash payments and other adjustments	(9.1		)	(7.8		)	(16.9		)
	Balance as of September 30, 2014	$	1.1		$	23.1		$	24.2
	Current							$	9.9
	Non-current							14.3
								$	24.2
		Severance			Lease			Total
		and Other			and Other
		Employee			Facility
		Costs			Costs
	Balance as of December 31, 2013	$	0.8		$	24.9		$	25.7
	Restructuring charges	9.8			6.7			16.5
	Reduction of prior restructuring accruals	(0.4		)	(0.7		)	(1.1		)
	Cash payments and other adjustments	(9.1		)	(7.8		)	(16.9		)
	Balance as of September 30, 2014	$	1.1		$	23.1		$	24.2
	Current							$	9.9
	Non-current							14.3
								$	24.2

GOODWILL_AND_INTANGIBLE_ASSETS1

GOODWILL AND INTANGIBLE ASSETS (Tables)	9 Months Ended
	Sep. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Changes in Carrying Amount of Goodwill	'
	The changes in the carrying amount of goodwill for the nine-month period ended September 30, 2014 and for the year ended December 31, 2013 are as follows:
		Clinical Diagnostics Laboratory Segment					Other Segment						Total
		September 30,		December 31, 2013			September 30,			December 31, 2013			September 30,			December 31, 2013
		2014					2014						2014
	Balance as of January 1	$	2,960.20	$	2,857.10		$	62.6		$	44.6		$	3,022.80		$	2,901.70
	Goodwill acquired during the period	46.7		107.5			—			19.5			46.7			127
	Adjustments to goodwill	—		(4.4		)	(3.1		)	(1.5		)	(3.1		)	(5.9		)
	Balance at end of period	$	3,006.90	$	2,960.20		$	59.5		$	62.6		$	3,066.40		$	3,022.80
Components of identifiable intangible assets	'
	The components of identifiable intangible assets are as follows:
		September 30, 2014								December 31, 2013
		Gross		Accumulated			Net			Gross			Accumulated			Net
		Carrying		Amortization						Carrying			Amortization
		Amount								Amount
	Customer relationships	$	1,337.90	$	(591.4	)	$	746.5		$	1,327.00		$	(545.1	)	$	781.9
	Patents, licenses and technology	120.7		(93.3		)	27.4			116.2			(85.4		)	30.8
	Non-compete agreements	44.6		(30.1		)	14.5			41.6			(25.3		)	16.3
	Trade names	131.3		(89.4		)	41.9			131.4			(83.0		)	48.4
	Canadian licenses	659.1		—			659.1			694.6			—			694.6
		$	2,293.60	$	(804.2	)	$	1,489.40		$	2,310.80		$	(738.8	)	$	1,572.00

DEBT_Tables

DEBT (Tables)	9 Months Ended
	Sep. 30, 2014
Debt Disclosure [Abstract]	'
Short-term borrowings and current portion of long-term debt	'
	Short-term borrowings and the current portion of long-term debt at September 30, 2014 and December 31, 2013 consisted of the following:
		September 30,		December 31, 2013
		2014
	Zero-coupon convertible subordinated notes	$	95.6	$	110.8
	Current portion of capital leases	2		0.5
	Total short-term borrowings and current portion of long-term debt	$	97.6	$	111.3
Long-term debt	'
	Long-term debt at September 30, 2014 and December 31, 2013 consisted of the following:
		September 30,		December 31, 2013
		2014
	5.625% senior notes due 2015	$	250	$	250
	3.125% senior notes due 2016	325		325
	2.20% senior notes due 2017	500		500
	2.50% senior notes due 2018	400		400
	4.625% senior notes due 2020	617		600
	3.75% senior notes due 2022	500		500
	4.00% senior notes due 2023	300		300
	Capital leases	25.1		14.1
	Total long-term debt	$	2,917.10	$	2,889.10

PREFERRED_STOCK_AND_COMMON_SHA1

PREFERRED STOCK AND COMMON SHAREHOLDERS' EQUITY (Tables)	9 Months Ended
	Sep. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'
Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]	'
	The components of accumulated other comprehensive earnings are as follows:
		Foreign				Net				Unrealized Gains and Losses on Available for Sale Securities			Accumulated
		Currency				Benefit							Other
		Translation				Plan							Comprehensive
		Adjustments				Adjustments							Earnings
	Balance at December 31, 2013	$	123.2			$	(67.1	)		$	10.1		$	66.2
	Other comprehensive earnings before reclassifications	(49.1		)		26.1				1.9			(21.1		)
	Amounts reclassified from accumulated other comprehensive earnings to the Condensed Consolidated Statement of Operations (a) (b)	—				(0.9		)		(20.3		)	(21.2		)
	Tax effect of adjustments	19				(9.7		)		7.1			16.4
	Balance at September 30, 2014	$	93.1			$	(51.6	)		$	(1.2	)	$	40.3
Changes in common shares issued and held in treasury	'
	The changes in common shares issued and held in treasury are summarized below:
		Issued			Held in			Outstanding
					Treasury
	Common shares at December 31, 2013	108.1			(22.4	)		85.7
	Common stock issued under employee stock plans	1.6			—			1.6
	Common stock issued upon conversion of zero-coupon subordinated notes	0.1			—			0.1
	Surrender of restricted stock and performance share awards	—			(0.1	)		(0.1	)
	Retirement of common stock	(2.4	)		—			(2.4	)
	Common shares at September 30, 2014	107.4			(22.5	)		84.9

PENSION_AND_POSTRETIREMENT_PLA1

PENSION AND POSTRETIREMENT PLANS (Tables)	9 Months Ended
	Sep. 30, 2014
Postemployment Benefits [Abstract]	'
Schedule of Pensions and Postretirement Plans	'
	The effect on operations of the post-retirement medical plan is shown in the following table:
		Three Months Ended September 30,						Nine Months Ended September 30,
		2014			2013			2014			2013
	Service cost for benefits earned	$	0.1		$	0.1		$	0.2		$	0.3
	Interest cost on benefit obligation	0.4			0.6			1.3			1.9
	Net amortization and deferral	(2.0		)	0.2			(5.9		)	0.7
	Post-retirement medical plan (benefit) costs	$	(1.5	)	$	0.9		$	(4.4	)	$	2.9
	In the first quarter of 2014, the Company made certain administrative changes to the Plan which resulted in an expected reduction in future post-retirement medical benefits. The resulting reduction to the post-retirement medical liability was inadvertently not recorded until the third quarter of 2014. As a result, an out of period adjustment of approximately $11.7 (after tax) was recorded to reduce the post-retirement medical liability and increase other comprehensive income. The Company concluded that the impact was not material to the current or prior periods.
	The effect on operations for the Company Plan and the PEP is summarized as follows:
		Three Months Ended September 30,						Nine Months Ended September 30,
		2014			2013			2014			2013
	Service cost for administrative expenses	$	0.8		$	0.7		$	2.5		$	1.9
	Interest cost on benefit obligation	4.2			3.7			12.3			11.1
	Expected return on plan assets	(4.6		)	(4.3		)	(13.6		)	(12.9		)
	Net amortization and deferral	1.6			2.3			5			8.3
	Defined benefit plan costs	$	2		$	2.4		$	6.2		$	8.4

FAIR_VALUE_MEASUREMENTS_Tables

FAIR VALUE MEASUREMENTS (Tables)	9 Months Ended
	Sep. 30, 2014
Fair Value Disclosures [Abstract]	'
Company's population of financial assets and liabilities subject to fair value measurements	'
	The Company’s population of financial assets and liabilities subject to fair value measurements as of September 30, 2014 and December 31, 2013 is as follows:
				Fair Value Measurements as of
		Fair Value		September 30, 2014
		as of		Using Fair Value Hierarchy
		September 30, 2014		Level 1		Level 2		Level 3
	Noncontrolling interest put	$	18.4	$	—	$	19.3	$	—
	Interest rate swap	17		—		17		—
	Cash surrender value of life insurance policies	40.8		—		40.8		—
	Deferred compensation liability	41.3		—		41.3		—
	Investment in equity securities	1		1		—		—
				Fair Value Measurements as of
		Fair Value		December 31, 2013
		as of		Using Fair Value Hierarchy
		December 31, 2013		Level 1		Level 2		Level 3
	Noncontrolling interest put	$	19.4	$	—	$	19.4	$	—
	Interest rate swap	—		—		—		—
	Cash surrender value of life insurance policies	35.1		—		35.1		—
	Deferred compensation liability	36.3		—		36.3		—
	Investment in equity securities	26.3		26.3		—		—

SUPPLEMENTAL_CASH_FLOW_INFORMA1

SUPPLEMENTAL CASH FLOW INFORMATION (Tables)	9 Months Ended
	Sep. 30, 2014
Supplemental Cash Flow Information [Abstract]	'
Supplemental Cash Flow Information	'
		Nine Months Ended September 30,
		2014			2013
	Supplemental schedule of cash flow information:
	Cash paid during period for:
	Interest	$	74.7		$	65.4
	Income taxes, net of refunds	211.1			228.1
	Disclosure of non-cash financing and investing activities:
	Surrender of restricted stock awards and performance awards	$	6.6		$	7.1
	Conversion of zero-coupon convertible debt	8.6			10.3
	Assets acquired under capital leases	13.1			9.8
	Increase (decrease) accrued property, plant and equipment	(3.3		)	1.8

BUSINESS_SEGMENT_INFORMATION_T

BUSINESS SEGMENT INFORMATION (Tables)	9 Months Ended
	Sep. 30, 2014
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]	'
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block]	'
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
		2014			2013			2014			2013
	Net revenues:
	Clinical diagnostics laboratory	$	1,468.90		$	1,377.80		$	4,250.50		$	4,113.40
	Other	82.9			84.4			248.4			257.9
	Total net revenues	1,551.80			1,462.20			4,498.90			4,371.30
	Operating earnings (loss):
	Clinical diagnostics laboratory	375.8			359.5			1,082.50			1,113.80
	Other	21.2			24			64.6			71.7
	General corporate expenses	(155.6		)	(138.9		)	(455.7		)	(409.6		)
	Total operating income	241.4			244.6			691.4			775.9
	Other income (expense), net	(22.4		)	(14.6		)	(52.2		)	(54.5		)
	Earnings before income taxes	219			230			639.2			721.4
	Provision for income taxes	81.5			81.3			246.5			272.7
	Net earnings	137.5			148.7			392.7			448.7
	Less income attributable to noncontrolling interests	(0.3		)	(0.4		)	(1.1		)	(1.2		)
	Net income attributable to Laboratory Corporation of America Holdings	$	137.2		$	148.3		$	391.6		$	447.5

BASIS_OF_FINANCIAL_STATEMENT_P1

BASIS OF FINANCIAL STATEMENT PRESENTATION (Details)	9 Months Ended
	Sep. 30, 2014
Accounting Policies [Abstract]	'
Ownership percentage below which investments are generally accounted for on the cost method (in thousandths)	20.00%

EARNINGS_PER_SHARE_Reconciliat

EARNINGS PER SHARE (Reconciliation of Basic Earnings Per Share to Diluted Earnings Per Share) (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, except Per Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Income [Abstract]	'	'	'	'
Net earnings, basic	$137.20	$148.30	$391.60	$447.50
Net earnings including impact of dilutive adjustments	$137.20	$148.30	$391.60	$447.50
Shares [Abstract]	'	'	'	'
Net earnings, basic (in shares)	84.9	89.2	84.9	91.4
Dilutive effect of employee stock options and awards, (in shares)	1.1	1.1	1.1	1
Effect of convertible debt, net of tax, (in shares)	0.5	'	0.5	0.6
Net earnings including impact of dilutive adjustments, (in shares)	86.5	90.9	86.5	93
Per Share Amount [Abstract]	'	'	'	'
Basic earnings per common share (in dollars per share)	$1.62	$1.66	$4.61	$4.90
Diluted earnings per common share (in dollars per share)	$1.59	$1.63	$4.53	$4.81

EARNINGS_PER_SHARE_Potential_c

EARNINGS PER SHARE (Potential common shares not included in computation of diluted earnings per share) (Details)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Earnings Per Share [Abstract]	'	'	'	'
Stock options (in shares)	0	0	0	0.4

RESTRUCTURING_AND_OTHER_SPECIA2

RESTRUCTURING AND OTHER SPECIAL CHARGES (Details) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Restructuring Cost and Reserve [Line Items]	'	'	'
Restructuring Reserve	$24.20	'	$25.70
Restructuring Charges	16.5	'	'
Restructuring Reserve Settled With Cash And Other Adjustment	-16.9	'	'
Net restructuring charges	15.4	17.8	'
Reduction in prior employee severance benefits related restructuring accruals	0.4	0.7	'
Reduction in prior facility related restructuring accruals	0.7	2.1	'
Other Special Charges	10.1	'	'
Restructuring charges related to severance and other employee costs	9.8	11.8	'
Restructuring charges related to contractual obligations associated with leased facilities and other facility related costs	6.7	8.8	'
Reduction in total prior restructuring accruals	-1.1	'	'
Restructuring Reserve, Current	9.9	'	'
Restructuring Reserve, Noncurrent	14.3	'	'
Employee Severance [Member]	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'
Restructuring Reserve	1.1	'	0.8
Restructuring Charges	9.8	'	'
Restructuring Reserve Settled With Cash And Other Adjustment	-9.1	'	'
Reduction in total prior restructuring accruals	-0.4	'	'
Facility Closing [Member]	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'
Restructuring Reserve	23.1	'	24.9
Restructuring Charges	6.7	'	'
Restructuring Reserve Settled With Cash And Other Adjustment	-7.8	'	'
Reduction in total prior restructuring accruals	($0.70)	'	'

RESTRUCTURING_RESERVES_Details

RESTRUCTURING RESERVES (Details) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Restructuring Cost and Reserve [Line Items]	'	'
Facility Related Restructuring Reserve Accrual Adjustment	$0.70	$2.10
Balance, beginning of period	25.7	'
Restructuring charges	16.5	'
Reduction of prior restructuring accruals	-1.1	'
Cash payments and other adjustments	-16.9	'
Balance, end of period	24.2	'
Current	9.9	'
Non-current	14.3	'
Total Restructuring Reserve	24.2	'
Severance and Other Employee Costs [Member]	'	'
Restructuring Cost and Reserve [Line Items]	'	'
Balance, beginning of period	0.8	'
Restructuring charges	9.8	'
Reduction of prior restructuring accruals	-0.4	'
Cash payments and other adjustments	-9.1	'
Balance, end of period	1.1	'
Total Restructuring Reserve	1.1	'
Lease and Other Facility Costs [Member]	'	'
Restructuring Cost and Reserve [Line Items]	'	'
Balance, beginning of period	24.9	'
Restructuring charges	6.7	'
Reduction of prior restructuring accruals	-0.7	'
Cash payments and other adjustments	-7.8	'
Balance, end of period	23.1	'
Total Restructuring Reserve	$23.10	'

GOODWILL_AND_INTANGIBLE_ASSETS2

GOODWILL AND INTANGIBLE ASSETS (Changes in Carrying Amount of Goodwill) (Details) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Goodwill [Line Items]	'	'
Balance as of January 1	$3,022.80	$2,901.70
Goodwill acquired during the period	46.7	127
Adjustments to goodwill	-3.1	-5.9
Balance at end of period	3,066.40	'
Clinical diagnostics laboratory [Member]	'	'
Goodwill [Line Items]	'	'
Balance as of January 1	2,960.20	2,857.10
Goodwill acquired during the period	46.7	107.5
Adjustments to goodwill	0	-4.4
Balance at end of period	3,006.90	'
Other Segments [Member]	'	'
Goodwill [Line Items]	'	'
Balance as of January 1	62.6	44.6
Goodwill acquired during the period	0	19.5
Adjustments to goodwill	-3.1	-1.5
Balance at end of period	$59.50	'

GOODWILL_AND_INTANGIBLE_ASSETS3

GOODWILL AND INTANGIBLE ASSETS (Components of identifiable intangible assets) (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	$2,293.60	$2,310.80
Accumulated Amortization	-804.2	-738.8
Intangible Assets, Net (Excluding Goodwill)	1,489.40	1,572
Customer Relationships [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	1,337.90	1,327
Accumulated Amortization	-591.4	-545.1
Intangible Assets, Net (Excluding Goodwill)	746.5	781.9
Patents, Licenses And Technology [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	120.7	116.2
Accumulated Amortization	-93.3	-85.4
Intangible Assets, Net (Excluding Goodwill)	27.4	30.8
Noncompete Agreements [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	44.6	41.6
Accumulated Amortization	-30.1	-25.3
Intangible Assets, Net (Excluding Goodwill)	14.5	16.3
Trade Names [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	131.3	131.4
Accumulated Amortization	-89.4	-83
Intangible Assets, Net (Excluding Goodwill)	41.9	48.4
Canadian licenses [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	659.1	694.6
Accumulated Amortization	0	0
Intangible Assets, Net (Excluding Goodwill)	$659.10	$694.60

GOODWILL_AND_INTANGIBLE_ASSETS4

GOODWILL AND INTANGIBLE ASSETS (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Mar. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'	'	'	'	'
Amortization of intangible assets	$18.30	$20.30	$61.30	$60.30	'
Finite-Lived Intangible Assets, Future Amortization Expense	'	'	'	'	'
Estimated amortization expense, 2012	'	'	'	'	20.1
Estimated amortization expense, 2013	'	'	'	'	82.6
Estimated amortization expense, 2014	'	'	'	'	77.3
Estimated amortization expense, 2015	'	'	'	'	70.1
Estimated amortization expense, 2016	'	'	'	'	59.3
Estimated amortization expense, Thereafter	'	'	'	'	$500.70

DEBT_Shortterm_borrowings_and_

DEBT (Short-term borrowings and current portion of long-term debt) (Table) (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Short-term Debt [Line Items]	'	'
Capital Lease Obligations, Current	$2	$0.50
Total short-term borrowings and current portion of long-term debt	97.6	111.3
Zero-coupon convertible subordinated notes [Member]	'	'
Short-term Debt [Line Items]	'	'
Total short-term borrowings and current portion of long-term debt	$95.60	$110.80

DEBT_Longterm_debt_Table_Detai

DEBT (Long-term debt) (Table) (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Nov. 19, 2010
In Millions, unless otherwise specified
Debt Instrument [Line Items]	'	'	'
Debt to EBITDA (Leverage) Ratio	2.5	'	'
Total long-term debt	$2,917.10	$2,889.10	'
Capital Lease Obligations	25.1	14.1	'
Capital lease obligation	2	0.5	'
Senior notes due 2013 [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Stated interest rate percentage	5.50%	'	'
Senior notes due 2015 [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Total long-term debt	250	250	'
Stated interest rate percentage	5.63%	'	'
Senior notes due 2016 [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Total long-term debt	325	325	'
Stated interest rate percentage	3.13%	'	'
Senior notes due 2017 [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Total long-term debt	500	500	'
Stated interest rate percentage	2.20%	'	'
Senior notes due 2018 [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Total long-term debt	400	400	'
Senior notes due 2020 [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Total long-term debt	617	'	'
Debt Instrument, Face Amount	'	600	'
Stated interest rate percentage	4.63%	'	4.63%
Senior notes due 2022 [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Total long-term debt	500	500	'
Stated interest rate percentage	3.75%	'	'
Senior notes due 2023 [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Total long-term debt	$300	$300	'

DEBT_Senior_Notes_Details

DEBT (Senior Notes) (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Nov. 19, 2010
In Millions, unless otherwise specified
Debt Instrument [Line Items]	'	'	'
Fair Value Hedges, Net	17	$0	'
Derivative, Basis Spread on Variable Rate	2.30%	'	'
Senior notes due 2022 [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Stated interest rate percentage	3.75%	'	'
Senior notes due 2017 [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Stated interest rate percentage	2.20%	'	'
Senior notes due 2020 [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Stated interest rate percentage	4.63%	'	4.63%
Debt Instrument, Face Amount	'	$600	'

DEBT_Convertible_Subordinated_

DEBT (Convertible Subordinated Notes) (Details) (USD $)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Zero Coupon Convertible Subordinated Notes [Line Items]	'	'
Payments on zero-coupon subordinated notes	($16,800,000)	($21,300,000)
Common stock issued upon conversion of zero-coupon subordinated notes (in shares)	100,000	'
Zero-coupon convertible subordinated notes [Member]	'	'
Zero Coupon Convertible Subordinated Notes [Line Items]	'	'
Principal amount at maturity of zero coupon subordinated notes converted	19,400,000	'
Value of cash and common stock in connection with conversions of zero coupon subordinated notes settled in current period	25,400,000	'
Payments on zero-coupon subordinated notes	-16,800,000	'
Minimum contingent cash interest rate on zero-coupon subordinated notes (in hundredths)	0.13%	'
Number of trading days used to establish contingent cash interest rate on zero-coupon subordinated notes (in days)	'5	'
Stock conversion rate for zero-coupon subordinated notes (per thousand)	13.4108	'
Principal amount of zero-coupon subordinated notes	$1,000	'
Date of the terms for the zero-coupon subordinated notes and indenture	24-Oct-06	'

DEBT_Credit_Facilities_Details

DEBT (Credit Facilities) (Details) (USD $)	9 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2014	Dec. 21, 2011	Dec. 31, 2013
	Quarters	Revolving Credit Facility [Member]	Unsecured Debt [Member]	Unsecured Debt [Member]	Revolving Credit Facility [Member]
			Revolving Credit Facility [Member]	Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]	'	'	'	'	'
Term for Revolving Credit Facility	'	'	'5 years	'	'
Revolving Credit Facility, maximum borrowing capacity	'	'	'	$1,000	'
Line of Credit Facility, Amount Outstanding	0	'	'	'	'
Revolving Credit Facility, outstanding balance	'	'	'	'	$0
Revolving Credit Facility, covenant compliance	'The Company was in compliance with all covenants in the Credit Agreement as of September 30, 2014.	'	'	'	'
Debt covenant, requirement for number of consecutive fiscal quarters	4	'	'	'	'
Debt to EBITDA (leverage) ratio	2.5	'	'	'	'
Revolving Credit Facility, interest rate at period end	'	1.13%	'	'	'
Line of Credit Facility, Covenant Terms	'The Credit Agreement also contains limitations on aggregate subsidiary indebtedness and a debt covenant that requires that the Company maintain on the last day of any period of four consecutive fiscal quarters, in each case taken as one accounting period, a ratio of total debt to consolidated EBITDA (Earnings Before Interest, Taxes, Depreciation, and Amortization) of not more than 3.0 to 1.0.	'	'	'	'
Revolving Credit Facility covenant terms ceiling	3	'	'	'	'

PREFERRED_STOCK_AND_COMMON_SHA2

PREFERRED STOCK AND COMMON SHAREHOLDERS' EQUITY (Details) (USD $)	9 Months Ended
In Millions, except Per Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Stockholders' Equity Note [Abstract]	'	'
Common stock, shares authorized	265	'
Common stock, par value per share (in dollars per share)	$0.10	'
Preferred stock, shares authorized	30	'
Preferred stock, par value per share (in dollars per share)	$0.10	'
Preferred stock, shares outstanding	0	'
Rollforward of common shares issued	'	'
Common shares issued, beginning balance (in shares)	108.1	'
Common stock issued under employee stock plans (in shares)	1.6	'
Common stock issued upon conversion of zero-coupon subordinated notes (in shares)	0.1	'
Retirement of common stock (in shares)	-2.4	'
Common shares issued, ending balance (in shares)	107.4	'
Rollforward of common shares held in treasury	'	'
Common shares held in Treasury, beginning balance (in shares)	-22.4	'
Common stock issued upon conversion of zero-coupon subordinated notes (in shares)	0.1	'
Surrender of restricted stock and performance share awards (in shares)	-0.1	'
Common shares held in Treasury, ending balance (in shares)	-22.5	'
Rollforward of common shares outstanding	'	'
Common shares outstanding, beginning balance (in shares)	85.7	'
Common stock issued under employee stock plans (in shares)	1.6	'
Common stock issued upon conversion of zero-coupon subordinated notes (in shares)	0.1	'
Surrender of restricted stock and performance share awards (in shares)	-0.1	'
Retirement of common stock (in shares)	-2.4	'
Common shares outstanding, ending balance (in shares)	84.9	'
Rollforward of Share Repurchase Program	'	'
Outstanding common stock repurchase authorization, beginning balance	$1,058.50	'
Common stock repurchased (in shares)	-2.4	'
Purchase of common stock	-229.9	-765.5
Outstanding common stock repurchase authorization, ending balance	$828.60	'

PREFERRED_STOCK_AND_COMMON_SHA3

PREFERRED STOCK AND COMMON SHAREHOLDERS' EQUITY PREFERRED STOCK AND COMMON SHAREHOLDERS' EQUITY - Accumulated Other Comprehensive Earnings (Details) (USD $)

3 Months Ended

9 Months Ended

In Millions, unless otherwise specified

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Dec. 31, 2013

Equity [Abstract]

'

'

'

'

'

Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]

'

'

'

'

'

The components of accumulated other comprehensive earnings are as follows:

Foreign

Net

Unrealized Gains and Losses on Available for Sale Securities

Accumulated

Currency

Benefit

Other

Translation

Plan

Comprehensive

Adjustments

Adjustments

Earnings

Balance at December 31, 2013

$

123.2

$

(67.1

)

$

10.1

$

66.2

Other comprehensive earnings before reclassifications

(49.1

)

26.1

1.9

(21.1

)

Amounts reclassified from accumulated other comprehensive earnings to the Condensed Consolidated Statement of Operations (a) (b)

—

(0.9

)

(20.3

)

(21.2

)

Tax effect of adjustments

19

(9.7

)

7.1

16.4

Balance at September 30, 2014

$

93.1

$

(51.6

)

$

(1.2

)

$

40.3

Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, before Tax

'

'

$0

'

'

Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Reclassification Adjustments and Tax

'

'

26.1

'

'

Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax

'

'

-20.3

'

'

Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax

'

'

21.2

[1]

'

'

Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax

'

'

1.9

'

'

Other Comprehensive Income (Loss), before Reclassifications, before Tax

'

'

-21.1

'

'

Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax

-1.2

'

-1.2

'

10.1

Accumulated Other Comprehensive Earnings [Roll Forward]

'

'

'

'

'

Foreign Currency Translation Adjustments, Beginning balance

'

'

123.2

'

'

Other comprehensive income before reclassifications

'

'

-49.1

'

'

Tax effect of adjustments

'

'

19

'

'

Foreign Currency Translation Adjustments, Ending balance

93.1

'

93.1

'

'

Net Benefit Plan Adjustments, Beginning balance

'

'

-67.1

'

'

Amounts reclassified from accumulated other comprehensive income

'

'

-0.9

[1]

'

'

Tax effect of adjustments

'

'

-9.7

'

'

Other Comprehensive Income (Loss), Available-for-sale Securities, Tax

'

'

7.1

'

'

Net Benefit Plan Adjustments, Ending balance

-51.6

'

-51.6

'

'

Accumulated Other Comprehensive Earnings, Beginning balance

'

'

66.2

'

'

Other comprehensive income before reclassifications

'

'

-49.1

'

'

Amounts reclassified from accumulated other comprehensive income

'

'

-0.9

[1]

'

'

Tax effect of adjustments

11.7

-9.5

16.4

10.4

'

Accumulated Other Comprehensive Earnings, Ending balance

$40.30

'

$40.30

'

'

[1]

The amortization of prior service cost is included in the computation of net periodic benefit cost. See NoteB 9 (Pension and Post-retirement Plans) below for additional information regarding the Company's net periodic benefit cost.

INCOME_TAXES_Details

INCOME TAXES (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Income Tax Disclosure [Abstract]	'	'
Minimum threshold percentage required to recognize income tax benefit (in hundredths)	50.00%	'
Gross unrecognized income tax benefits	$21.90	$25.60
Unrecognized income tax benefits that would impact effective tax rate	21.9	25.6
Accrued interest and penalties related to unrecognized income tax benefits	8.8	9.3
Valuation allowance provided for deferred tax assets	$18.10	$16.50

COMMITMENTS_AND_CONTINGENCIES_

COMMITMENTS AND CONTINGENCIES (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Jun. 30, 2011	Sep. 30, 2014	Aug. 24, 2012
				Recipients
Loss Contingencies [Line Items]	'	'	'	'
Litigation settlement expense in connection with the California False Claims Act lawsuit	'	$34,500,000	'	'
Previously recorded litigation reserve in connection with the California False Claims Act lawsuit	'	15,000,000	'	'
Litigation Settlement, Gross	49.5	'	'	'
Loss Contingency, Damages Awarded, Value	'	'	50,000,000	'
Loss Contingency Damages Awarded Gross	'	'	20,800,000	'
Number of Recipients	'	'	'	39
Proposed damages per violation	'	'	'	0.0005
Loss Contingency Damages Awarded Net	'	'	15,800,000	'
Reduction for Plaintiff Negligence	'	'	25.00%	'
Company's apportioned responsibility	'	'	50.00%	'
Co-defendant's apportioned responsibility	'	'	50.00%	'
Loss contingency reduced damages awarded gross	'	'	5,000,000	'
Loss contingency reduced damages awarded net	'	'	4,400,000	'
Letters of Credit Outstanding, Amount	'	'	$42,500,000	'
Tri-State Clinical Laboratory Services, LLC [Member]	'	'	'	'
Loss Contingencies [Line Items]	'	'	'	'
Ownership interest percentage, parent	'	50.00%	'	'

PENSION_AND_POSTRETIREMENT_PLA2

PENSION AND POSTRETIREMENT PLANS (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Defined Benefit Plan Disclosures [Line Items]	'	'	'	'
Pension Contributions	'	'	$0	'
Minimum non-elective contribution (NEC) % for the 401(K) plan (in hundredths)	'	'	3.00%	'
Discretionary contribution % for the 401(K) plan, range mininum	'	'	1.00%	'
Discretionary contribution % for the 401(K) plan, range maximum	'	'	3.00%	'
Defined contribution retirement plan cost	12.6	12.2	38.8	37.3
Defined Benefit Plans [Member]	'	'	'	'
Defined Benefit Plan and Postretirement Plan Disclosure	'	'	'	'
Service cost for benefits earned	0.8	0.7	2.5	1.9
Interest cost on benefit obligation	4.2	3.7	12.3	11.1
Expected return on plan assets	-4.6	-4.3	-13.6	-12.9
Net amortization and deferral	1.6	2.3	5	8.3
Defined benefit/postretirement plan costs	2	2.4	6.2	8.4
Post-Retirement Medical Plan [Member]	'	'	'	'
Defined Benefit Plan and Postretirement Plan Disclosure	'	'	'	'
Service cost for benefits earned	0.1	0.1	0.2	0.3
Interest cost on benefit obligation	0.4	0.6	1.3	1.9
Net amortization and deferral	-2	0.2	-5.9	0.7
Defined benefit/postretirement plan costs	($1.50)	$0.90	($4.40)	$2.90

PENSION_AND_POSTRETIREMENT_PLA3

PENSION AND POSTRETIREMENT PLANS Defined Contribution Plans (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Contribution Plan, Cost Recognized	$12.60	$12.20	$38.80	$37.30

FAIR_VALUE_MEASUREMENTS_Detail

FAIR VALUE MEASUREMENTS (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]	'	'
Noncontrolling interest puts	$18.40	$19.40
Fair market value of zero-coupon subordinated notes	152.3	155.5
Fair market value of senior notes	2,956.80	2,907.80
Cash Surrender Value, Fair Value Disclosure	40.8	35.1
Fair Value Liabilities Measured On Recurring Basis Deferred Compensation Liability	41.3	36.3
Investments, Fair Value Disclosure	1	26.3
Level 1 [Member]	'	'
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]	'	'
Noncontrolling interest puts	0	0
Interest Rate Fair Value Hedge Asset at Fair Value	0	0
Cash Surrender Value, Fair Value Disclosure	0	0
Fair Value Liabilities Measured On Recurring Basis Deferred Compensation Liability	0	0
Investments, Fair Value Disclosure	1	26.3
Level 2 [Member]	'	'
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]	'	'
Noncontrolling interest puts	19.3	19.4
Interest Rate Fair Value Hedge Derivative at Fair Value, Net	17	0
Cash Surrender Value, Fair Value Disclosure	40.8	35.1
Fair Value Liabilities Measured On Recurring Basis Deferred Compensation Liability	41.3	36.3
Investments, Fair Value Disclosure	0	0
Level 3 [Member]	'	'
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]	'	'
Noncontrolling interest puts	0	0
Interest Rate Fair Value Hedge Derivative at Fair Value, Net	0	0
Cash Surrender Value, Fair Value Disclosure	0	0
Fair Value Liabilities Measured On Recurring Basis Deferred Compensation Liability	0	0
Investments, Fair Value Disclosure	$0	$0

DERIVATIVE_INSTRUMENTS_AND_HED1

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (Details) (USD $)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	Sep. 30, 2014	Dec. 31, 2013	Nov. 19, 2010
	Embedded_Derivative_Instruments			Senior notes due 2020 [Member]	Senior notes due 2020 [Member]	Senior notes due 2020 [Member]
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'	'	'
Debt Instrument, Interest Rate, Stated Percentage	'	'	'	4.63%	'	4.63%
Debt Instrument, Face Amount	'	'	'	'	$600,000,000	'
Derivative, Basis Spread on Variable Rate	2.30%	'	'	'	'	'
Fair Value Hedges, Net	17,000,000	'	0	'	'	'
Number of features considered to be embedded derivative instruments	2	'	'	'	'	'
Minimum percentage of market price to calculated value of zero-coupon subordinated debt at which the entity is subject to contingent cash interest	120.00%	'	'	'	'	'
Embedded derivative, fair value	0	'	'	'	'	'
Embedded derivative, impact on condensed consolidated statements of operations	$0	$0	'	'	'	'

SUPPLEMENTAL_CASH_FLOW_INFORMA2

SUPPLEMENTAL CASH FLOW INFORMATION (Details) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Debt Conversion [Line Items]	'	'
Noncash conversion of zero-coupon convertible debt	$8.60	$10.30
Fair Value of Assets Acquired	13.1	9.8
Increase (Decrease) in Accrued Liabilities	-3.3	1.8
Cash paid during period for:	'	'
Interest	74.7	65.4
Income taxes, net of refunds	211.1	228.1
Restricted Stock Awards And Performance Shares Surrendered	$6.60	$7.10

BUSINESS_ACQUISITIONS_Details

BUSINESS ACQUISITIONS (Details) (USD $)	9 Months Ended
In Millions, except Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	Dec. 31, 2012	Nov. 02, 2014
					Covance, Inc. [Member]
Business Acquisition [Line Items]	'	'	'	'	'
Significant Acquisitions and Disposals, Acquisition Costs or Sale Proceeds	'	'	'	'	$6,100
Goodwill	3,066.40	'	3,022.80	2,901.70	'
Cash payments for laboratory-related assets	157.2	142.6	'	'	'
Business Acquisition, Share Price	'	'	'	'	$75.76
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned	'	'	'	'	0.2686
Acquiree's shareholder's ownership of stock post acquisition	'	'	'	'	0.00%
Anticipated financing for proposed acquisition	'	'	'	'	$4,250

BUSINESS_ACQUISITIONS_Business

BUSINESS ACQUISITIONS Business Acquisitions in the Aggregate (Details) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Business Acquisition [Line Items]	'	'
Payments to Acquire Businesses, Net of Cash Acquired	$65.30	$109
Finite-lived Intangible Assets Acquired	15.6	'
Goodwill, Acquired During Period	$46.70	$127

BUSINESS_SEGMENT_INFORMATION_B1

BUSINESS SEGMENT INFORMATION Business Segment Information (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Segment Reporting Information [Line Items]	'	'	'	'
Total net revenues	$1,551.80	$1,462.20	$4,498.90	$4,371.30
Total operating income	241.4	244.6	691.4	775.9
Non-operating expenses, net	-22.4	-14.6	-52.2	-54.5
Earnings before income taxes	219	230	639.2	721.4
Provision for income taxes	81.5	81.3	246.5	272.7
Net earnings	137.5	148.7	392.7	448.7
Less income attributable to noncontrolling interests	-0.3	-0.4	-1.1	-1.2
Net income attributable to Laboratory Corporation of America Holdings	137.2	148.3	391.6	447.5
Clinical diagnostics laboratory [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total net revenues	1,468.90	1,377.80	4,250.50	4,113.40
Total operating income	375.8	359.5	1,082.50	1,113.80
General corporate expenses [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total operating income	-155.6	-138.9	-455.7	-409.6
Other Segments [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total net revenues	82.9	84.4	248.4	257.9
Total operating income	$21.20	$24	$64.60	$71.70