O'Reilly Automotive (ORLY) 10-Q 8 May 15 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2015	4-May-15
Document and Entity Information
Document type	10-Q
Amendment flag	FALSE
Document period end date	31-Mar-15
Document fiscal year focus	2015
Current fiscal year end date	-19
Document fiscal period focus	Q1
Entity registrant name	O REILLY AUTOMOTIVE INC
Entity central index key	898173
Entity filer category	Large Accelerated Filer
Entity common stock, shares outstanding		100,989,965

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Assets
Cash and cash equivalents	$473,646	$250,560	[1]
Accounts receivable, net	162,020	143,900	[1]
Amounts receivable from suppliers	69,545	69,311	[1]
Inventory	2,527,982	2,554,789	[1]
Other current assets	40,928	48,418	[1]
Total current assets	3,274,121	3,066,978	[1]
Property and equipment, at cost	4,080,350	3,993,509	[1]
Less: accumulated depreciation and amortization	1,381,502	1,334,949	[1]
Net property and equipment	2,698,848	2,658,560	[1]
Notes receivable, less current portion	12,414	13,349	[1]
Goodwill	756,384	756,384	[1]
Other assets, net	43,943	45,030	[1]
Total assets	6,785,710	6,540,301	[1]
Liabilities and shareholders' equity
Accounts payable	2,470,749	2,417,167	[1]
Self-insurance reserves	67,676	64,882	[1]
Accrued payroll	75,059	78,442	[1]
Accrued benefits and withholdings	42,413	62,946	[1]
Deferred income taxes	16,651	17,258	[1]
Income taxes payable	78,939	0	[1]
Other current liabilities	200,888	189,836	[1]
Current portion of long-term debt	6	25	[1]
Total current liabilities	2,952,381	2,830,556	[1]
Long-term debt, less current portion	1,396,741	1,396,615	[1]
Deferred income taxes	81,330	85,164	[1]
Other liabilities	211,758	209,548	[1]
Shareholders' equity:
Common stock, $0.01 par value: Authorized shares - 245,000,000 Issued and outstanding shares - 101,347,744 as of March 31, 2015, and 101,602,935 as of December 31, 2014	1,013	1,016	[1]
Additional paid-in capital	1,234,133	1,194,929	[1]
Retained earnings	908,354	822,473	[1]
Total shareholders' equity	2,143,500	2,018,418	[1]
Total liabilities and shareholders' equity	$6,785,710	$6,540,301	[1]
[1]	The balance sheet at December 31, 2014, has been derived from the audited consolidated financial statements at that date, but does not include all of the information and footnotes required by United States generally accepted accounting principles for complete financial statements.

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	245,000,000	245,000,000
Common stock, shares issued	101,347,744	101,602,935
Common stock, shares outstanding	101,347,744	101,602,935

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Income (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
Sales	$1,901,903	$1,727,943
Cost of goods sold, including warehouse and distribution expenses	914,944	850,227
Gross profit	986,959	877,716
Selling, general and administrative expenses	636,586	590,596
Operating income	350,373	287,120
Other income (expense):
Interest expense	-14,402	-13,409
Interest income	580	631
Other, net	1,113	618
Total other expense	-12,709	-12,160
Income before income taxes	337,664	274,960
Provision for income taxes	124,800	101,100
Net income	$212,864	$173,860
Earnings per share-basic:
Earnings per share - basic	$2.09	$1.64
Weighted-average common shares outstanding - basic	101,612	106,191
Earnings per share-assuming dilution:
Earnings per share - assuming dilution	$2.06	$1.61
Weighted-average common shares outstanding - assuming dilution	103,257	108,070

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Cash Flows (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Operating activities:
Net income	$212,864		$173,860
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of property, equipment and intangibles	54,950		47,477
Amortization of debt discount and issuance costs	525		520
Excess tax benefit from stock options exercised	-21,188		-17,850
Deferred income taxes	-4,441		-3,796
Share-based compensation programs	5,890		5,096
Other	1,355		1,526
Changes in operating assets and liabilities:
Accounts receivable	-19,867		-13,016
Inventory	26,807		-21,994
Accounts payable	53,582		104,376
Income taxes payable	117,221		69,922
Other	-21,673		-572
Net cash provided by operating activities	406,025		345,549
Investing activities:
Purchases of property and equipment	-91,140		-83,085
Proceeds from sale of property and equipment	658		287
Payments received on notes receivable	935		900
Net cash used in investing activities	-89,547		-81,898
Financing activities:
Principal payments on capital leases	-19		-18
Repurchases of common stock	-134,813		-22,067
Excess tax benefit from stock options exercised	21,188		17,850
Net proceeds from issuance of common stock	20,252		21,097
Net cash (used in) provided by financing activities	-93,392		16,862
Net increase in cash and cash equivalents	223,086		280,513
Cash and cash equivalents at beginning of the period	250,560	[1]	231,318
Cash and cash equivalents at end of the period	473,646		511,831
Supplemental disclosures of cash flow information:
Income taxes paid	8,675		33,331
Interest paid, net of capitalized interest	$23,435		$22,419
[1]	The balance sheet at December 31, 2014, has been derived from the audited consolidated financial statements at that date, but does not include all of the information and footnotes required by United States generally accepted accounting principles for complete financial statements.

Basis_of_Presentation

Basis of Presentation	3 Months Ended
	Mar. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of presentation	NOTE 1 - BASIS OF PRESENTATION
	The accompanying unaudited condensed consolidated financial statements of O'Reilly Automotive, Inc. and its subsidiaries (the "Company" or "O'Reilly") have been prepared in accordance with United States generally accepted accounting principles ("U.S. GAAP") for interim financial information and the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. Operating results for the three months ended March 31, 2015, are not necessarily indicative of the results that may be expected for the year ended December 31, 2015. For further information, refer to the consolidated financial statements and footnotes thereto included in the Company's Annual Report on Form 10-K for the year ended December 31, 2014.

Fair_Value_Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Fair value measurements	NOTE 2 – FAIR VALUE MEASUREMENTS
	The Company uses the fair value hierarchy, which prioritizes the inputs used to measure the fair value of certain of its financial instruments. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurement) and the lowest priority to unobservable inputs (Level 3 measurement). The Company uses the income and market approaches to determine the fair value of its assets and liabilities. The three levels of the fair value hierarchy are set forth below:
	•	Level 1 – Quoted prices (unadjusted) in active markets for identical assets or liabilities that the reporting entity can access at the measurement date.
	•	Level 2 – Inputs other than quoted prices in active markets included within Level 1 that are observable for the asset or liability, either directly or indirectly.
	•	Level 3 – Unobservable inputs for the asset or liability.
	Financial assets and liabilities measured at fair value on a recurring basis:
	The carrying amount of the Company's marketable securities is included in "Other assets, net" on the accompanying Condensed Consolidated Balance Sheets as of March 31, 2015, and December 31, 2014. The Company recorded $0.4 million of appreciation in fair value related to its marketable securities, which is included in "Other income (expense)" on the accompanying Condensed Consolidated Statements of Income, for the three months ended March 31, 2015.
	The table below identifies the estimated fair value of the Company's marketable securities, determined by reference to quoted market prices (Level 1), as of March 31, 2015, and December 31, 2014 (in thousands):
		Quoted Prices in Active Markets for Identical Instruments				Significant Other Observable Inputs				Significant Unobservable Inputs				Total
		(Level 1)				(Level 2)				(Level 3)
		31-Mar-15		31-Dec-14		31-Mar-15		31-Dec-14		31-Mar-15		31-Dec-14		31-Mar-15		31-Dec-14
	Marketable securities	$	16,656	$	15,378	$	—	$	—	$	—	$	—	$	16,656	$	15,378
	Non-financial assets and liabilities measured at fair value on a nonrecurring basis:
	Certain long-lived non-financial assets and liabilities may be required to be measured at fair value on a nonrecurring basis in certain circumstances, including when there is evidence of impairment. These non-financial assets and liabilities may include assets acquired in a business combination or property and equipment that are determined to be impaired. As of March 31, 2015, and December 31, 2014, the Company did not have any non-financial assets or liabilities that had been measured at fair value subsequent to initial recognition.
	Fair value of financial instruments:
	The carrying amounts of the Company's senior notes are included in "Long-term debt, less current portion" on the accompanying Condensed Consolidated Balance Sheets as of March 31, 2015, and December 31, 2014. See Note 3 for further discussion on the Company's senior notes.
	The table below identifies the estimated fair value of the Company's senior notes, using the market approach. The fair values as of March 31, 2015, and December 31, 2014, were determined by reference to quoted market prices of the same or similar instruments (Level 2) (in thousands):
		March 31, 2015				December 31, 2014
		Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value
	4.875% Senior Notes due 2021	$	497,964	$	558,055	$	497,876	$	566,700
	4.625% Senior Notes due 2021	299,663		331,769		299,650		337,222
	3.800% Senior Notes due 2022	299,134		314,468		299,109		310,749
	3.850% Senior Notes due 2023	$	299,980	$	314,806	$	299,980	$	311,656
	The accompanying Condensed Consolidated Balance Sheets include other financial instruments, including cash and cash equivalents, accounts receivable, amounts receivable from suppliers and accounts payable. Due to the short-term nature of these financial instruments, the Company believes that the carrying values of these instruments approximate their fair values.

LongTerm_Debt

Long-Term Debt	3 Months Ended
	Mar. 31, 2015
Debt Disclosure [Abstract]
Long-term debt	NOTE 3 – LONG-TERM DEBT
	The following table identifies the amounts included in "Current portion of long-term debt" and "Long-term debt, less current portion" on the accompanying Condensed Consolidated Balance Sheets as of March 31, 2015, and December 31, 2014 (in thousands):
		March 31, 2015		December 31, 2014
	Revolving Credit Facility	$	—	$	—
	4.875% Senior Notes due 2021(1), effective interest rate of 4.966%	497,964		497,876
	4.625% Senior Notes due 2021(2), effective interest rate of 4.648%	299,663		299,650
	3.800% Senior Notes due 2022(3), effective interest rate of 3.845%	299,134		299,109
	3.850% Senior Notes due 2023(4), effective interest rate of 3.851%	299,980		299,980
	Capital leases	6		25
	Total debt and capital lease obligations	1,396,747		1,396,640
	Current portion of long-term debt	6		25
	Long-term debt, less current portion	$	1,396,741	$	1,396,615
	(1)	Net of unamortized discount of $2.0 million as of March 31, 2015, and $2.1 million as of December 31, 2014.
	(2)	Net of unamortized discount of $0.3 million as of March 31, 2015, and $0.4 million as of December 31, 2014.
	(3)	Net of unamortized discount of $0.9 million as of March 31, 2015, and December 31, 2014.
	(4)	Net of unamortized discount of less than $0.1 million as of March 31, 2015, and December 31, 2014.
	Unsecured revolving credit facility:
	On January 14, 2011, the Company entered into a credit agreement, as amended by Amendment No. 1 dated as of September 9, 2011, and as further amended by Amendment No. 2 dated as of July 2, 2013 (the "Credit Agreement"). The Credit Agreement provides for a $600 million unsecured revolving credit facility (the "Revolving Credit Facility") arranged by Bank of America, N.A., which is scheduled to mature in July of 2018. The Credit Agreement includes a $200 million sub-limit for the issuance of letters of credit and a $75 million sub-limit for swing line borrowings under the Revolving Credit Facility. As described in the Credit Agreement governing the Revolving Credit Facility, the Company may, from time to time, subject to certain conditions, increase the aggregate commitments under the Revolving Credit Facility by up to $200 million. As of March 31, 2015, and December 31, 2014, the Company had outstanding letters of credit, primarily to support obligations related to workers' compensation, general liability and other insurance policies, in the amount of $50.5 million and $47.9 million, respectively, reducing the aggregate availability under the Revolving Credit Facility by those amounts. As of March 31, 2015, and December 31, 2014, the Company had no outstanding borrowings under the Revolving Credit Facility.
	Borrowings under the Revolving Credit Facility (other than swing line loans) bear interest, at the Company's option, at the Base Rate or Eurodollar Rate (both as defined in the Credit Agreement) plus an applicable margin. Swing line loans made under the Revolving Credit Facility bear interest at the Base Rate plus the applicable margin for Base Rate loans. In addition, the Company pays a facility fee on the aggregate amount of the commitments in an amount equal to a percentage of such commitments. The interest rate margins and facility fee are based upon the better of the ratings assigned to the Company's debt by Moody's Investor Service, Inc. and Standard & Poor's Ratings Services, subject to limited exceptions. As of March 31, 2015, based upon the Company's credit ratings, its margin for Base Rate loans was 0.000%, its margin for Eurodollar Rate loans was 0.875% and its facility fee was 0.125%.
	The Credit Agreement contains certain covenants, including limitations on indebtedness, a minimum consolidated fixed charge coverage ratio of 2.50 times through maturity, and a maximum consolidated leverage ratio of 3.00 times through maturity. The consolidated leverage ratio includes a calculation of adjusted debt to earnings before interest, taxes, depreciation, amortization, rent and non-cash share-based compensation expense. Adjusted debt includes outstanding debt, outstanding stand-by letters of credit and similar instruments, six-times rent expense and excludes any premium or discount recorded in conjunction with the issuance of long-term debt. In the event that the Company should default on any covenant contained within the Credit Agreement, certain actions may be taken, including, but not limited to, possible termination of commitments, immediate payment of outstanding principal amounts plus accrued interest and other amounts payable under the Credit Agreement and litigation from lenders. As of March 31, 2015, the Company remained in compliance with all covenants under the Credit Agreement.
	Senior notes:
	The Company has issued $1.4 billion aggregate principal amount of unsecured senior notes due between 2021 and 2023 with United Missouri Bank, N.A. as trustee. Interest on the senior notes, ranging from 3.800% to 4.875%, is payable biannually and is computed on the basis of a 360-day year.
	The senior notes are guaranteed on a senior unsecured basis by each of the Company's subsidiaries ("Subsidiary Guarantors") that incurs or guarantees obligations under the Company's Credit Agreement or under other credit facility or capital markets debt of the Company's or any of the Company's Subsidiary Guarantors. The guarantees are joint and several and full and unconditional, subject to certain customary automatic release provisions, including release of the Subsidiary Guarantor's guarantee under the Company's Credit Agreement and certain other debt, or, in certain circumstances, the sale or other disposition of a majority of the voting power of the capital interest in, or of all or substantially all of the property of, the Subsidiary Guarantor.  Each of the Subsidiary Guarantors is 100% owned, directly or indirectly, by the Company and the Company has no independent assets or operations other than those of its subsidiaries. The only direct or indirect subsidiaries of the Company that would not be Subsidiary Guarantors would be minor subsidiaries. Neither the Company, nor any of its Subsidiary Guarantors, is subject to any material or significant restrictions on the Company's ability to obtain funds from its subsidiaries by dividend or loan or to transfer assets from such subsidiaries, except as provided by applicable law. Each of the senior notes is subject to certain customary covenants, with which the Company complied as of March 31, 2015.

Warranties

Warranties	3 Months Ended
	Mar. 31, 2015
Product Warranties Disclosures [Abstract]
Warranties	NOTE 4 – WARRANTIES
	The Company provides warranties on certain merchandise it sells with warranty periods ranging from 30 days to limited lifetime warranties. The risk of loss arising from warranty claims is typically the obligation of the Company's suppliers. Certain suppliers provide upfront allowances to the Company in lieu of accepting the obligation for warranty claims. For this merchandise, when sold, the Company bears the risk of loss associated with the cost of warranty claims. Differences between supplier allowances received by the Company in lieu of warranty obligations and estimated warranty expense are recorded as an adjustment to cost of sales. Estimated warranty costs, which are recorded as obligations at the time of sale, are based on the historical failure rate of each individual product line. The Company's historical experience has been that failure rates are relatively consistent over time and that the ultimate cost of warranty claims to the Company has been driven by volume of units sold as opposed to fluctuations in failure rates or the variation of the cost of individual claims.
	The Company's product warranty liabilities are included in "Other current liabilities" on the accompanying Condensed Consolidated Balance Sheets as of March 31, 2015, and December 31, 2014. The following table identifies the changes in the Company's aggregate product warranty liabilities for the three months ended March 31, 2015 (in thousands):
	Balance at December 31, 2014	$	34,226
	Warranty claims	(10,733		)
	Warranty accruals	8,616
	Balance at March 31, 2015	$	32,109

Share_Repurchase_Program

Share Repurchase Program	3 Months Ended
	Mar. 31, 2015
Proceeds from (Repurchase of) Equity [Abstract]
Share repurchase program	NOTE 5 – SHARE REPURCHASE PROGRAM
	In January of 2011, the Company's Board of Directors approved a share repurchase program. Under the program, the Company may, from time to time, repurchase shares of its common stock, solely through open market purchases effected through a broker dealer at prevailing market prices, based on a variety of factors such as price, corporate trading policy requirements and overall market conditions. The Company and its Board of Directors may increase or otherwise modify, renew, suspend or terminate the share repurchase program at any time, without prior notice. As announced on February 4, 2015, the Company's Board of Directors approved a resolution to increase the authorization amount under the share repurchase program by an additional $500 million, resulting in a cumulative authorization amount of $5.0 billion. The additional $500 million authorization is effective for a three-year period, beginning on its announcement date.
	The following table identifies shares of the Company's common stock that have been repurchased as part of the Company's publicly announced share repurchase program (in thousands, except per share data):
		For the Three Months Ended
		March 31,
		2015		2014
	Shares repurchased	650		149
	Average price per share	$	207.5	$	148.18
	Total investment	$	134,803	$	22,065
	As of March 31, 2015, the Company had $644.5 million remaining under its share repurchase program. Subsequent to the end of the first quarter and through May 8, 2015, the Company repurchased an additional 0.6 million shares of its common stock under its share repurchase program, at an average price of $218.25, for a total investment of $133.9 million. The Company has repurchased a total of 47.6 million shares of its common stock under its share repurchase program since the inception of the program in January of 2011 and through May 8, 2015, at an average price of $94.29, for a total aggregate investment of $4.5 billion.

ShareBased_Compensation_and_Be

Share-Based Compensation and Benefit Plans	3 Months Ended
	Mar. 31, 2015
Employee Benefits and Share-based Compensation [Abstract]
Share-based compensation and benefit plans	NOTE 6 – SHARE-BASED COMPENSATION AND BENEFIT PLANS
	The Company recognizes share-based compensation expense based on the fair value of the grants, awards or shares at the time of the grant, award or issuance. Share-based compensation includes stock option awards issued under the Company's employee incentive plans and director stock plan, restricted stock awarded under the Company's employee incentive plans, performance incentive plan and director stock plan, stock issued through the Company's employee stock purchase plan and stock awarded to employees through other benefit programs.
	Stock options:
	The Company's stock-based incentive plans provide for the granting of stock options for the purchase of common stock of the Company to directors and certain key employees of the Company. Options are granted at an exercise price that is equal to the closing market price of the Company's common stock on the date of the grant. Director options granted under the plans expire after seven years and are fully vested after six months. Employee options granted under the plans expire after ten years and typically vest 25% per year, over four years. The Company records compensation expense for the grant date fair value of the option awards, adjusted for estimated forfeitures, evenly over the minimum required service period.
	The table below identifies stock option activity under these plans during the three months ended March 31, 2015:
		Shares			Weighted-Average
		(in thousands)			Exercise Price
	Outstanding at December 31, 2014	4,065			$	64.57
	Granted	209			200.96
	Exercised	(377	)		46.3
	Forfeited	(28	)		86.31
	Outstanding at March 31, 2015	3,869			$	73.58
	Exercisable at March 31, 2015	2,566			$	48.16
	The fair value of each stock option award is estimated on the date of the grant using the Black-Scholes option pricing model. The Black-Scholes model requires the use of assumptions, including the risk free rate, expected life, expected volatility and expected dividend yield.
	•	Risk-free interest rate – The United States Treasury rates in effect at the time the options are granted for the options' expected life.
	•
	•	Expected life - Represents the period of time that options granted are expected to be outstanding. The Company uses historical experience to estimate the expected life of options granted.
	•	Expected volatility – Measure of the amount by which the Company's stock price has historically fluctuated.
	•	Expected dividend yield – The Company has not paid, nor does it have plans in the foreseeable future to pay, any dividends.
	The table below identifies the weighted-average assumptions used for grants awarded during the three months ended March 31, 2015 and 2014:
		For the Three Months Ended
		March 31,
		2015				2014
	Risk free interest rate	1.57	%			1.74	%
	Expected life	6.1		Years		5.9		Years
	Expected volatility	22.4	%			25.5	%
	Expected dividend yield	—	%			—	%
	The Company's forfeiture rate is the estimated percentage of options awarded that are expected to be forfeited or canceled prior to becoming fully vested. The Company's estimate is evaluated periodically and is based upon historical experience at the time of evaluation and reduces expense ratably over the vesting period or the minimum required service period.
	The following table summarizes activity related to stock options awarded by the Company for the three months ended March 31, 2015 and 2014 (in thousands, except per share data):
		For the Three Months Ended
		March 31,
		2015				2014
	Compensation expense for stock options awarded	$	4,997			$	4,085
	Income tax benefit from compensation expense related to stock options	1,847				1,512
	Weighted-average grant-date fair value of options awarded	$	51.57			$	39.13
	The remaining unrecognized compensation expense related to unvested stock option awards at March 31, 2015, was $33.5 million and the weighted-average period of time over which this cost will be recognized is 2.7 years.
	Other share-based compensation plans:
	The Company sponsors other share-based compensation plans: an employee stock purchase plan (the "ESPP"), which permits all eligible employees to purchase shares of the Company’s common stock at 85% of the fair market value; a performance incentive plan, which provides for the award of shares of restricted stock to its corporate and senior management that vest evenly over a three-year period and are held in escrow until such vesting has occurred; and a director stock plan, which provides for the award of shares of restricted stock to the Company's independent directors that vest evenly over a three-year period and are held in escrow until such vesting has occurred. The fair value of shares awarded under these plans is based on the closing market price of the Company's common stock on the date of award, and compensation expense is recorded evenly over the minimum required service period.
	The table below summarizes activity related to the Company's other share-based compensation plans for the three months ended March 31, 2015 and 2014 (in thousands):
		For the Three Months Ended
		March 31,
		2015				2014
	Compensation expense for shares issued under the ESPP	$	489			$	438
	Income tax benefit from compensation expense related to shares issued under the ESPP	181				162
	Compensation expense for restricted shares awarded	404				573
	Income tax benefit from compensation expense related to restricted awards	$	149			$	212
	Profit sharing and savings plan:
	The Company sponsors a contributory profit sharing and savings plan (the "401(k) Plan") that covers substantially all employees who are at least 21 years of age and have at least six months of service. The Company makes matching contributions equal to 100% of the first 2% of each employee's wages that are contributed and 25% of the next 4% of each employee's wages that are contributed. An employee must be employed on December 31 to receive that year's Company matching contribution, with the matching contribution funded annually in the January following the year in which the matching contribution was earned. The Company may also make additional discretionary profit sharing contributions to the plan on an annual basis as determined by the Board of Directors. The Company did not make any discretionary contributions to the 401(k) Plan during the three months ended March 31, 2015 or 2014. The Company expensed matching contributions under the 401(k) Plan in the amounts of $4.2 million and $3.9 million for the three months ended March 31, 2015 and 2014, respectively.
	Nonqualified deferred compensation plan:
	The Company sponsors a nonqualified deferred compensation plan (the "Deferred Compensation Plan") for highly compensated employees whose contributions to the 401(k) Plan are limited due to the application of the annual limitations under the Internal Revenue Code. The Deferred Compensation Plan provides these employees with the opportunity to defer compensation that was precluded under the Company's 401(k) Plan due to the annual limitations, including salary and incentive based compensation, which is then matched by the Company using the same formula as the 401(k) Plan. An employee must be employed on December 31 to receive that year's Company matching contribution, with the matching contribution funded annually in the January following the year in which the matching contribution was earned. In the event of bankruptcy, the assets of this plan are available to satisfy the claims of general creditors. The Company has an unsecured obligation to pay, in the future, the value of the deferred compensation and Company match adjusted to reflect the performance, whether positive or negative, of selected investment measurement options chosen by each participant during the deferral period. The liability for compensation deferred under the Deferred Compensation Plan was $16.7 million and $15.4 million as of March 31, 2015, and December 31, 2014, respectively, and was included within "Other liabilities" on the Condensed Consolidated Balance Sheets. The Company expensed matching contributions under the Deferred Compensation Plan in the amounts of less than $0.1 million and $0.1 million for the three months ended March 31, 2015 and 2014, respectively.

Earnings_Per_Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2015
Earnings Per Share [Abstract]
Earnings per share	NOTE 7 – EARNINGS PER SHARE
	The following table illustrates the computation of basic and diluted earnings per share for the three months ended March 31, 2015 and 2014 (in thousands, except per share data):
		For the Three Months Ended
		March 31,
		2015		2014
	Numerator (basic and diluted):
	Net income	$	212,864	$	173,860
	Denominator:
	Denominator for basic earnings per share - weighted-average shares	101,612		106,191
	Effect of stock options (1)	1,645		1,879
	Denominator for diluted earnings per share - weighted-average shares	103,257		108,070
	Earnings per share:
	Earnings per share-basic	$	2.09	$	1.64
	Earnings per share-assuming dilution	$	2.06	$	1.61
	Antidilutive potential common shares not included in the calculation of diluted earnings per share:
	Stock options (1)	278		288
	Weighted-average exercise price per share of antidilutive stock options (1)	$	195.9	$	135.22
	(1)	See Note 6 for further discussion on the terms of the Company's share-based compensation plans.
	For the three months ended March 31, 2015 and 2014, the computation of diluted earnings per share did not include certain securities. These securities represent underlying stock options not included in the computation of diluted earnings per share, because the inclusion of such equity awards would have been antidilutive.
	Subsequent to the end of the first quarter and through May 8, 2015, the Company repurchased 0.6 million shares of its common stock, at an average price of $218.25, for a total investment of $133.9 million.

Legal_Matters

Legal Matters	3 Months Ended
	Mar. 31, 2015
Loss Contingency [Abstract]
Legal matters	NOTE 8 – LEGAL MATTERS
	O'Reilly is currently involved in litigation incidental to the ordinary conduct of the Company's business. The Company records reserves for litigation losses in instances where a material adverse outcome is probable and the Company is able to reasonably estimate the probable loss. The Company reserves for an estimate of material legal costs to be incurred in pending litigation matters. Although the Company cannot ascertain the amount of liability that it may incur from any of these matters, it does not currently believe that, in the aggregate, these matters, taking into account applicable insurance and reserves, will have a material adverse effect on its consolidated financial position, results of operations or cash flows in a particular quarter or annual period.
	As previously reported, the Company received a subpoena from the District Attorney of the County of Alameda, along with other environmental prosecutorial offices in the state of California, seeking documents and information related to the handling, storage and disposal of hazardous waste. Management has an ongoing and open dialogue with these agencies regarding this matter and is cooperating fully with the request; however, at this time a prediction of the ultimate outcome of these efforts cannot be determined.

Recent_Accounting_Pronouncemen

Recent Accounting Pronouncements	3 Months Ended
	Mar. 31, 2015
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recent accounting pronouncements	NOTE 9 - RECENT ACCOUNTING PRONOUNCEMENTS
	In May of 2014, the Financial Accounting Standards Board (the "FASB") issued Accounting Standard Update ("ASU") No. 2014-09, "Revenue from Contracts with Customers (Topic 606)" ("ASU 2014-09"). Under ASU 2014-09, an entity is required to follow a five-step process to determine the amount of revenue to recognize when promised goods or services are transferred to customers. ASU 2014-09 offers specific accounting guidance for costs to obtain or fulfill a contract with a customer. In addition, an entity is required to disclose sufficient information to understand the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. For public companies, ASU 2014-09 is effective for annual reporting periods beginning after December 15, 2016, including periods within that reporting period, and can be adopted either retrospectively or as a cumulative effect adjustment at the date of adoption, with early adoption not permitted. The Company will adopt this guidance beginning with its first quarter ending March 31, 2017. The Company is in the process of evaluating the potential future impact, if any, of ASU 2014-09 on its consolidated financial position, results of operations and cash flows.
	In January of 2015, the FASB issued ASU No. 2015-01, "Extraordinary and Unusual Items (Subtopic 225-20)" ("ASU 2015-01"). ASU 2015-01 eliminates from generally accepted accounting principles the concept of extraordinary items; such that, an entity will no longer need to assess whether a particular event or transaction event is extraordinary. ASU 2015-01 is effective for annual reporting periods beginning after December 15, 2015, including periods within that reporting period, and early adoption is permitted. The Company will adopt this guidance beginning with its first quarter ending March 31, 2016. The application of this guidance is not expected to have a material impact on the Company's consolidated financial condition, results of operations or cash flows.
	In April of 2015, the FASB issued ASU No. 2015-03, "Interest - Imputation of Interest (Subtopic 835-30)" ("ASU 2015-03"). ASU 2015-03 requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability. ASU 2015-03 is effective for annual reporting periods beginning after December 15, 2015, including periods within that reporting period, requires retrospective application, and early adoption is permitted. The Company will adopt this guidance with its first quarter ending March 31, 2016. The application of this guidance affects classification only, and therefore, it is not expected to have a material impact on the Company's consolidated financial condition, results of operations or cash flows.

Fair_Value_Measurements_Polici

Fair Value Measurements (Policies)	3 Months Ended
	Mar. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Fair value of financial instruments, policy	The Company uses the fair value hierarchy, which prioritizes the inputs used to measure the fair value of certain of its financial instruments. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurement) and the lowest priority to unobservable inputs (Level 3 measurement). The Company uses the income and market approaches to determine the fair value of its assets and liabilities.

Warranties_Policies

Warranties (Policies)	3 Months Ended
	Mar. 31, 2015
Product Warranties Disclosures [Abstract]
Warranties, policy	The Company provides warranties on certain merchandise it sells with warranty periods ranging from 30 days to limited lifetime warranties. The risk of loss arising from warranty claims is typically the obligation of the Company's suppliers. Certain suppliers provide upfront allowances to the Company in lieu of accepting the obligation for warranty claims. For this merchandise, when sold, the Company bears the risk of loss associated with the cost of warranty claims. Differences between supplier allowances received by the Company in lieu of warranty obligations and estimated warranty expense are recorded as an adjustment to cost of sales. Estimated warranty costs, which are recorded as obligations at the time of sale, are based on the historical failure rate of each individual product line. The Company's historical experience has been that failure rates are relatively consistent over time and that the ultimate cost of warranty claims to the Company has been driven by volume of units sold as opposed to fluctuations in failure rates or the variation of the cost of individual claims.

Recent_Accounting_Pronouncemen1

Recent Accounting Pronouncements Recent Accounting Pronouncements (Policies)	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
Recent accounting pronouncements, policy	In May of 2014, the Financial Accounting Standards Board (the "FASB") issued Accounting Standard Update ("ASU") No. 2014-09, "Revenue from Contracts with Customers (Topic 606)" ("ASU 2014-09"). Under ASU 2014-09, an entity is required to follow a five-step process to determine the amount of revenue to recognize when promised goods or services are transferred to customers. ASU 2014-09 offers specific accounting guidance for costs to obtain or fulfill a contract with a customer. In addition, an entity is required to disclose sufficient information to understand the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. For public companies, ASU 2014-09 is effective for annual reporting periods beginning after December 15, 2016, including periods within that reporting period, and can be adopted either retrospectively or as a cumulative effect adjustment at the date of adoption, with early adoption not permitted. The Company will adopt this guidance beginning with its first quarter ending March 31, 2017. The Company is in the process of evaluating the potential future impact, if any, of ASU 2014-09 on its consolidated financial position, results of operations and cash flows.
	In January of 2015, the FASB issued ASU No. 2015-01, "Extraordinary and Unusual Items (Subtopic 225-20)" ("ASU 2015-01"). ASU 2015-01 eliminates from generally accepted accounting principles the concept of extraordinary items; such that, an entity will no longer need to assess whether a particular event or transaction event is extraordinary. ASU 2015-01 is effective for annual reporting periods beginning after December 15, 2015, including periods within that reporting period, and early adoption is permitted. The Company will adopt this guidance beginning with its first quarter ending March 31, 2016. The application of this guidance is not expected to have a material impact on the Company's consolidated financial condition, results of operations or cash flows.
	In April of 2015, the FASB issued ASU No. 2015-03, "Interest - Imputation of Interest (Subtopic 835-30)" ("ASU 2015-03"). ASU 2015-03 requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability. ASU 2015-03 is effective for annual reporting periods beginning after December 15, 2015, including periods within that reporting period, requires retrospective application, and early adoption is permitted. The Company will adopt this guidance with its first quarter ending March 31, 2016. The application of this guidance affects classification only, and therefore, it is not expected to have a material impact on the Company's consolidated financial condition, results of operations or cash flows.

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Valuation of marketable securities
		Quoted Prices in Active Markets for Identical Instruments				Significant Other Observable Inputs				Significant Unobservable Inputs				Total
		(Level 1)				(Level 2)				(Level 3)
		31-Mar-15		31-Dec-14		31-Mar-15		31-Dec-14		31-Mar-15		31-Dec-14		31-Mar-15		31-Dec-14
	Marketable securities	$	16,656	$	15,378	$	—	$	—	$	—	$	—	$	16,656	$	15,378
Valuation of senior notes
		March 31, 2015				December 31, 2014
		Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value
	4.875% Senior Notes due 2021	$	497,964	$	558,055	$	497,876	$	566,700
	4.625% Senior Notes due 2021	299,663		331,769		299,650		337,222
	3.800% Senior Notes due 2022	299,134		314,468		299,109		310,749
	3.850% Senior Notes due 2023	$	299,980	$	314,806	$	299,980	$	311,656

LongTerm_Debt_Tables

Long-Term Debt (Tables)	3 Months Ended
	Mar. 31, 2015
Debt Disclosure [Abstract]
Outstanding long-term debt and capital lease obligations
		March 31, 2015		December 31, 2014
	Revolving Credit Facility	$	—	$	—
	4.875% Senior Notes due 2021(1), effective interest rate of 4.966%	497,964		497,876
	4.625% Senior Notes due 2021(2), effective interest rate of 4.648%	299,663		299,650
	3.800% Senior Notes due 2022(3), effective interest rate of 3.845%	299,134		299,109
	3.850% Senior Notes due 2023(4), effective interest rate of 3.851%	299,980		299,980
	Capital leases	6		25
	Total debt and capital lease obligations	1,396,747		1,396,640
	Current portion of long-term debt	6		25
	Long-term debt, less current portion	$	1,396,741	$	1,396,615
	(1)	Net of unamortized discount of $2.0 million as of March 31, 2015, and $2.1 million as of December 31, 2014.
	(2)	Net of unamortized discount of $0.3 million as of March 31, 2015, and $0.4 million as of December 31, 2014.
	(3)	Net of unamortized discount of $0.9 million as of March 31, 2015, and December 31, 2014.
	(4)	Net of unamortized discount of less than $0.1 million as of March 31, 2015, and December 31, 2014.

Warranties_Tables

Warranties (Tables)	3 Months Ended
	Mar. 31, 2015
Product Warranties Disclosures [Abstract]
Product warranty liabilities
	Balance at December 31, 2014	$	34,226
	Warranty claims	(10,733		)
	Warranty accruals	8,616
	Balance at March 31, 2015	$	32,109

Share_Repurchase_Program_Table

Share Repurchase Program (Tables)	3 Months Ended
	Mar. 31, 2015
Proceeds from (Repurchase of) Equity [Abstract]
Schedule of shares repurchased
		For the Three Months Ended
		March 31,
		2015		2014
	Shares repurchased	650		149
	Average price per share	$	207.5	$	148.18
	Total investment	$	134,803	$	22,065

ShareBased_Compensation_and_Be1

Share-Based Compensation and Benefit Plans (Tables)	3 Months Ended
	Mar. 31, 2015
Stock Option [Member]
Summary of stock options
		Shares			Weighted-Average
		(in thousands)			Exercise Price
	Outstanding at December 31, 2014	4,065			$	64.57
	Granted	209			200.96
	Exercised	(377	)		46.3
	Forfeited	(28	)		86.31
	Outstanding at March 31, 2015	3,869			$	73.58
	Exercisable at March 31, 2015	2,566			$	48.16
Black-Scholes option pricing model
		For the Three Months Ended
		March 31,
		2015				2014
	Risk free interest rate	1.57	%			1.74	%
	Expected life	6.1		Years		5.9		Years
	Expected volatility	22.4	%			25.5	%
	Expected dividend yield	—	%			—	%
Summary of activity of share-based compensation
		For the Three Months Ended
		March 31,
		2015				2014
	Compensation expense for stock options awarded	$	4,997			$	4,085
	Income tax benefit from compensation expense related to stock options	1,847				1,512
	Weighted-average grant-date fair value of options awarded	$	51.57			$	39.13
Restricted Stock [Member] | Employee Stock Purchase Plan [Member]
Summary of activity of share-based compensation
		For the Three Months Ended
		March 31,
		2015				2014
	Compensation expense for shares issued under the ESPP	$	489			$	438
	Income tax benefit from compensation expense related to shares issued under the ESPP	181				162
	Compensation expense for restricted shares awarded	404				573
	Income tax benefit from compensation expense related to restricted awards	$	149			$	212

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2015
Earnings Per Share [Abstract]
Computation of basic and diluted earnings per share
		For the Three Months Ended
		March 31,
		2015		2014
	Numerator (basic and diluted):
	Net income	$	212,864	$	173,860
	Denominator:
	Denominator for basic earnings per share - weighted-average shares	101,612		106,191
	Effect of stock options (1)	1,645		1,879
	Denominator for diluted earnings per share - weighted-average shares	103,257		108,070
	Earnings per share:
	Earnings per share-basic	$	2.09	$	1.64
	Earnings per share-assuming dilution	$	2.06	$	1.61
	Antidilutive potential common shares not included in the calculation of diluted earnings per share:
	Stock options (1)	278		288
	Weighted-average exercise price per share of antidilutive stock options (1)	$	195.9	$	135.22
	(1)	See Note 6 for further discussion on the terms of the Company's share-based compensation plans.

Fair_Value_Measurements_Narrat

Fair Value Measurements (Narrative) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Appreciation in fair value of marketable securities	$0.40
Non-financial assets and liabilities measured at fair value on a nonrecurring basis	$0	$0

Fair_Value_Measurements_Fair_V

Fair Value Measurements Fair Value Measurements (Fair Value of Marketable Securities) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Fair Value Measurements
Estimated fair value of marketable securities	$16,656	$15,378
Fair value, inputs, Level 1 [Member]
Fair Value Measurements
Estimated fair value of marketable securities	16,656	15,378
Fair value, inputs, Level 2 [Member]
Fair Value Measurements
Estimated fair value of marketable securities	0	0
Fair value, inputs, Level 3 [Member]
Fair Value Measurements
Estimated fair value of marketable securities	$0	$0

Fair_Value_Measurements_Fair_V1

Fair Value Measurements (Fair Value of Senior Notes) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Senior Notes due 2021 at 4.875% [Member]
Carrying amount of senior notes	$497,964	$497,876
Estimated fair value of senior notes	558,055	566,700
Senior Notes due 2021 at 4.625% [Member]
Carrying amount of senior notes	299,663	299,650
Estimated fair value of senior notes	331,769	337,222
Senior Notes due 2022 at 3.800% [Member]
Carrying amount of senior notes	299,134	299,109
Estimated fair value of senior notes	314,468	310,749
Senior Notes due 2023 at 3.850% [Member]
Carrying amount of senior notes	299,980	299,980
Estimated fair value of senior notes	$314,806	$311,656

LongTerm_Debt_Unsecured_Revolv

Long-Term Debt (Unsecured Revolving Credit Facility) (Details) (Unsecured debt [Member], Line of credit facility [Member], USD $)	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
	Rate
Credit agreement inception date	14-Jan-11
Current maximum borrowing capacity under credit facility	$600,000,000
Line of credit facility expiration date	2-Jul-18
Maximum aggregate increase to credit facility	200,000,000
Letters of credit	50,500,000	47,900,000
Outstanding borrowings under credit facility	0	0
Covenant description for debt instrument	The Credit Agreement contains certain covenants, including limitations on indebtedness, a minimum consolidated fixed charge coverage ratio of 2.50 times through maturity, and a maximum consolidated leverage ratio of 3.00 times through maturity. The consolidated leverage ratio includes a calculation of adjusted debt to earnings before interest, taxes, depreciation, amortization, rent and non-cash share-based compensation expense. Adjusted debt includes outstanding debt, outstanding stand-by letters of credit and similar instruments, six-times rent expense and excludes any premium or discount recorded in conjunction with the issuance of long-term debt. In the event that the Company should default on any covenant contained within the Credit Agreement, certain actions may be taken, including, but not limited to, possible termination of commitments, immediate payment of outstanding principal amounts plus accrued interest and other amounts payable under the Credit Agreement and litigation from lenders.
Line of credit facility fee percentage	0.13%
Line of credit facility covenant compliance	As of March 31, 2015, the Company remained in compliance with all covenants under the Credit Agreement.
Amendment one [Member]
Credit agreement amendment date	9-Sep-11
Amendment two [Member]
Credit agreement amendment date	2-Jul-13
Letter of credit [Member]
Line of credit facility sublimit	200,000,000
Swing line revolver [Member]
Line of credit facility sublimit	$75,000,000
Spread over Eurodollar rate [Member]
Line of credit current interest rate	0.88%
Spread over Base rate [Member]
Line of credit current interest rate	0.00%
Through maturity [Member]
Minimum debt instrument consolidated fixed charge coverage ratio covenant	2.5
Maximum debt instrument consolidated leverage ratio covenant	3

LongTerm_Debt_Senior_Notes_Det

Long-Term Debt (Senior Notes) (Details) (USD $)	3 Months Ended
In Billions, unless otherwise specified	Mar. 31, 2015
	D
	Rate
Aggregate principle of unsecured senior notes	$1.40
Interest rate of notes, minimum	3.80%
Interest rate of notes, maximum	4.88%
Number of days in annual interest calculation period	360
Debt instrument covenant description	Each of the senior notes is subject to certain customary covenants, with which the Company complied as of March 31, 2015.

LongTerm_Debt_Outstanding_Long

Long-Term Debt (Outstanding Long-Term Debt) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Revolving Credit Facility	$0	$0
Capital leases	6,000	25,000
Total debt and capital lease obligation	1,396,747,000	1,396,640,000
Current portion of long-term debt	6,000	25,000	[1]
Long-term debt, less current portion	1,396,741,000	1,396,615,000	[1]
Senior Notes due 2021 at 4.875% [Member]
Senior notes	497,964,000	497,876,000
Senior notes, unamortized discount	2,000,000	2,100,000
Effective interest rate	4.97%
Senior Notes due 2021 at 4.625% [Member]
Senior notes	299,663,000	299,650,000
Senior notes, unamortized discount	300,000	400,000
Effective interest rate	4.65%
Senior Notes due 2022 at 3.800% [Member]
Senior notes	299,134,000	299,109,000
Senior notes, unamortized discount	900,000	900,000
Effective interest rate	3.85%
Senior Notes due 2023 at 3.850% [Member]
Senior notes	299,980,000	299,980,000
Senior notes, unamortized discount	$100,000	$100,000
Effective interest rate	3.85%
[1]	The balance sheet at December 31, 2014, has been derived from the audited consolidated financial statements at that date, but does not include all of the information and footnotes required by United States generally accepted accounting principles for complete financial statements.

Warranties_Product_Warranty_Li

Warranties (Product Warranty Liabilities) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015
Product Warranties Disclosures [Abstract]
Balance at December 31, 2014	$34,226
Warranty claims	-10,733
Warranty accruals	8,616
Balance at March 31, 2015	$32,109

Share_Repurchase_Program_Narra

Share Repurchase Program (Narrative) (Details) (USD $)	0 Months Ended	3 Months Ended		1 Months Ended	52 Months Ended
Share data in Thousands, except Per Share data, unless otherwise specified	Feb. 04, 2015	Mar. 31, 2015	Mar. 31, 2014	8-May-15	8-May-15
Share repurchase program
Increase in authorized amount	$500,000,000
Cumulative authorized amount	5,000,000,000
Authorization effective period	3 years
Remaining balance under share repurchase program		644,500,000
Common stock repurchased, shares		650	149
Common stock repurchased, average price per share		$207.50	$148.18
Common stock repurchased, value		134,803,000	22,065,000
Subsequent Event [Member]
Share repurchase program
Common stock repurchased, shares				600	47,600
Common stock repurchased, average price per share				$218.25	$94.29
Common stock repurchased, value				$133,900,000	$4,500,000,000

Share_Repurchase_Program_Sched

Share Repurchase Program (Schedule Of Shares Repurchased) (Details) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Proceeds from (Repurchase of) Equity [Abstract]
Shares repurchased	650	149
Average price per share	$207.50	$148.18
Total investment	$134,803	$22,065

ShareBased_Compensation_and_Be2

Share-Based Compensation and Benefit Plans (Stock Option Narrative) (Details) (Stock Option [Member], USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015
Vesting of options description	The Company's stock-based incentive plans provide for the granting of stock options for the purchase of common stock of the Company to directors and certain key employees of the Company. Options are granted at an exercise price that is equal to the closing market price of the Company's common stock on the date of the grant. Director options granted under the plans expire after seven years and are fully vested after six months. Employee options granted under the plans expire after ten years and typically vest 25% per year, over four years. The Company records compensation expense for the grant date fair value of the option awards, adjusted for estimated forfeitures, evenly over the minimum required service period.
Remaining unrecognized compensation expense	$33.50
Weighted-average period for cost recognition	2 years 8 months 8 days
Director [Member]
Options expiration date	7 years
Vesting period	6 months
Employee Stock Option [Member]
Options expiration date	10 years
Vesting period	4 years
Option vesting rate per year	25.00%

ShareBased_Compensation_and_Be3

Share-Based Compensation and Benefit Plans (Other Share-Based Compensation) (Narrative) (Details)	3 Months Ended
	Mar. 31, 2015
	Rate
Employee Stock Purchase Plan [Member]
Other employee benefit plan description	an employee stock purchase plan (the "ESPP"), which permits all eligible employees to purchase shares of the Company’s common stock at 85% of the fair market value
Employee stock purchase plan stock purchase percentage	85.00%
Restricted Stock [Member]
Other employee benefit plan description	a performance incentive plan, which provides for the award of shares of restricted stock to its corporate and senior management that vest evenly over a three-year period and are held in escrow until such vesting has occurred; and a director stock plan, which provides for the award of shares of restricted stock to the Company's independent directors that vest evenly over a three-year period and are held in escrow until such vesting has occurred. The fair value of shares awarded under these plans is based on the closing market price of the Company's common stock on the date of award, and compensation expense is recorded evenly over the minimum required service period
Vesting period	3 years

ShareBased_Compensation_and_Be4

Share-Based Compensation and Benefit Plans (Summary Of Stock Options) (Details) (Stock Option [Member], USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015
Stock Option [Member]
Outstanding at December 31, 2014, shares	4,065
Outstanding at December 31, 2014, weighted-average exercise price	$64.57
Granted, shares	209
Granted, weighted-average exercise price	$200.96
Exercised, shares	-377
Exercised, weighted-average exercise price	$46.30
Forfeited, shares	-28
Forfeited, weighted-average exercise price	$86.31
Outstanding at March 31, 2015, shares	3,869
Outstanding at March 31, 2015, weighted-average exercise price	$73.58
Exercisable at March 31, 2015, shares	2,566
Exercisable at March 31, 2015, weighted-average exercise price	$48.16

ShareBased_Compensation_and_Be5

Share-Based Compensation and Benefit Plans (Black-Scholes Option Pricing Model) (Details) (Stock Option [Member])	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
	Rate	Rate
Stock Option [Member]
Risk-free interest rate	1.57%	1.74%
Expected life	6 years 1 month 6 days	5 years 10 months 15 days
Expected volatility	22.40%	25.50%
Expected dividend yield	0.00%	0.00%

ShareBased_Compensation_and_Be6

Share-Based Compensation and Benefit Plans (Stock Option Activity) (Details) (Stock Option [Member], USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Stock Option [Member]
Compensation expense for benefit plans	$4,997	$4,085
Income tax benefit from compensation expense for benefit plans	$1,847	$1,512
Weighted-average grant date fair value of options awarded	$51.57	$39.13

ShareBased_Compensation_and_Be7

Share-Based Compensation and Benefit Plans (Other Share-Based Compensation Activity) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Employee Stock Purchase Plan [Member]
Compensation expense for benefit plans	$489	$438
Income tax benefit from compensation expense for benefit plans	181	162
Restricted Stock [Member]
Compensation expense for benefit plans	404	573
Income tax benefit from compensation expense for benefit plans	$149	$212

ShareBased_Compensation_and_Be8

Share-Based Compensation and Benefit Plans (Profit Sharing and Savings Plan) (Narrative) (Details) (Profit Sharing And Savings Plan [Member], USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Profit Sharing And Savings Plan [Member]
Share-Based Compensation and Benefit Plans
Other employee benefit plan description	The Company sponsors a contributory profit sharing and savings plan (the "401(k) Plan") that covers substantially all employees who are at least 21 years of age and have at least six months of service. The Company makes matching contributions equal to 100% of the first 2% of each employee's wages that are contributed and 25% of the next 4% of each employee's wages that are contributed.
Profit sharing and savings plan employer discretionary contribution	$0	$0
Profit sharing and savings plan cost recognized	$4.20	$3.90

ShareBased_Compensation_and_Be9

Share-Based Compensation and Benefit Plans (Nonqualified Deferred Compensation Plan) (Narrative) (Details) (Nonqualified Deferred Compensation Plan [Member], USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Nonqualified Deferred Compensation Plan [Member]
Share-Based Compensation and Benefit Plans
Deferred compensation plan description	The Company sponsors a nonqualified deferred compensation plan (the "Deferred Compensation Plan") for highly compensated employees whose contributions to the 401(k) Plan are limited due to the application of the annual limitations under the Internal Revenue Code. The Deferred Compensation Plan provides these employees with the opportunity to defer compensation that was precluded under the Company's 401(k) Plan due to the annual limitations, including salary and incentive based compensation, which is then matched by the Company using the same formula as the 401(k) Plan.
Deferred compensation plan obligation	$16.70		$15.40
Deferred compensation plan cost recognized	$0.10	$0.10

Earnings_Per_Share_Narrative_D

Earnings Per Share (Narrative) (Details) (USD $)	3 Months Ended		1 Months Ended	52 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	8-May-15	8-May-15
Earnings Per Share
Common stock repurchased, shares	650	149
Common stock repurchased, average price per share	$207.50	$148.18
Common stock repurchased, value	$134,803	$22,065
Subsequent Event [Member]
Earnings Per Share
Common stock repurchased, shares			600	47,600
Common stock repurchased, average price per share			$218.25	$94.29
Common stock repurchased, value			$133,900	$4,500,000

Earnings_Per_Share_Computation

Earnings Per Share (Computation of Basic and Diluted Earnings Per Share) (Details) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Numerator (basic and diluted):
Net income	$212,864		$173,860
Denominator:
Denominator for basic earnings per share - weighted-average shares	101,612		106,191
Effect of stock options	1,645	[1]	1,879	[1]
Denominator for diluted earnings per share - weighted-average shares	103,257		108,070
Earnings per share - basic	$2.09		$1.64
Earnings per share - assuming dilution	$2.06		$1.61
Antidilutive stock options	278	[1]	288	[1]
Weighted-average exercise price	$195.90	[1]	$135.22	[1]
[1]	See Note 6 for further discussion on the terms of the Company's share-based compensation plans.