Catamaran 10-Q 1 Nov 13 2013 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2013	Oct. 31, 2013
Document Information [Line Items]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Sep-13	'
Document Fiscal Year Focus	'2013	'
Document Fiscal Period Focus	'Q3	'
Trading Symbol	'CTRX	'
Entity Registrant Name	'Catamaran Corp.	'
Entity Central Index Key	'0001363851	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	206,298,320

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Current assets	'	'
Cash and cash equivalents	$436,227	$370,776
Restricted cash	32,219	52,422
Accounts receivable, net of allowance for doubtful accounts of $6,532 (2012 — $7,899)	847,924	725,809
Rebates receivable	291,182	302,461
Other current assets	113,784	101,311
Total current assets	1,721,336	1,552,779
Property and equipment, net of accumulated depreciation of $91,915 (2012 — $64,048)	172,868	105,201
Goodwill	4,497,621	4,478,038
Other intangible assets, net of accumulated amortization of $307,721 (2012 — $178,188)	1,054,523	1,198,991
Other long-term assets	46,538	50,118
Total assets	7,492,886	7,385,127
Current liabilities	'	'
Accounts payable	693,625	644,818
Accrued expenses and other current liabilities	241,452	254,811
Pharmacy benefit management rebates payable	314,565	302,065
Current portion - long-term debt	43,750	41,250
Total current liabilities	1,293,392	1,242,944
Deferred income taxes	302,527	344,232
Long-term debt	976,610	1,132,153
Other long-term liabilities	87,694	55,937
Total liabilities	2,660,223	2,775,266
Commitments and contingencies (Note 11)	'	'
Shareholders’ equity	'	'
Common shares: no par value, unlimited shares authorized; 206,298,320 shares issued and outstanding, September 30, 2013 (December 31, 2012 — 205,399,102 shares)	4,215,139	4,180,778
Additional paid-in capital	72,825	73,530
Retained earnings	542,755	354,991
Accumulated other comprehensive loss	-1,997	-2,191
Total shareholders' equity	4,828,722	4,607,108
Non-controlling interest	3,941	2,753
Total equity	4,832,663	4,609,861
Total liabilities and equity	$7,492,886	$7,385,127

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parentheticals) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, except Share data, unless otherwise specified
Allowance for Doubtful Accounts Receivable, Current	$6,532	$7,899
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	91,915	64,048
Accumulated Amortization	$307,721	$178,188
Common Stock, Par or Stated Value Per Share	$0	$0
Common Stock, Shares, Issued	206,298,320	205,399,102
Common Stock, Shares, Outstanding	206,298,320	205,399,102

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenue	$3,614,148	$3,190,780	$10,251,295	$6,610,580
Cost of revenue	3,326,360	2,955,889	9,450,546	6,142,796
Gross profit	287,788	234,891	800,749	467,784
Expenses:	'	'	'	'
Selling, general and administrative	110,454	133,716	310,839	255,088
Depreciation of property and equipment	9,979	5,717	24,887	10,552
Amortization of intangible assets	47,220	51,380	147,368	70,710
Total operating expenses	167,653	190,813	483,094	336,350
Operating income	120,135	44,078	317,655	131,434
Interest and other expense, net	9,026	11,843	30,972	15,064
Income before income taxes	111,109	32,235	286,683	116,370
Income tax expense (benefit):	'	'	'	'
Current	38,419	30,816	111,841	62,004
Deferred	-10,438	-17,988	-36,225	-18,693
Total income tax expense (benefit)	27,981	12,828	75,616	43,311
Net income	83,128	19,407	211,067	73,059
Less: Net income (loss) attributable to non-controlling interest	10,190	-1,070	23,303	-1,070
Net income attributable to the Company	$72,938	$20,477	$187,764	$74,129
Earnings per share attributable to the Company:	'	'	'	'
Basic (in dollars per share)	$0.35	$0.10	$0.91	$0.48
Diluted (in dollars per share)	$0.35	$0.10	$0.91	$0.48
Weighted average number of shares used in computing earnings per share:	'	'	'	'
Basic (in shares)	206,203,263	203,505,355	205,920,803	153,850,043
Diluted (in shares)	206,824,618	204,439,048	206,636,923	154,977,182

Consolidated_Statement_of_Comp

Consolidated Statement of Comprehensive Income (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Net income	$83,128	$19,407	$211,067	$73,059
Other comprehensive income, net of tax	'	'	'	'
Unrealized income (loss) on cash flow hedge, net of income tax expense of $368 for the nine month period ended September 30, 2013	-853	-2,504	194	-2,504
Comprehensive income	82,275	16,903	211,261	70,555
Less: Comprehensive income (loss) attributable to non-controlling interest	10,190	-1,070	23,303	-1,070
Comprehensive income attributable to the Company	$72,085	$17,973	$187,958	$71,625

Recovered_Sheet1

Consolidated Statement Of Comprehensive (Parenthetical) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013
Statement of Other Comprehensive Income [Abstract]	'
Unrealized income (loss) on cash flow hedge, net of income tax expense of $368 for the nine month period ended September 30, 2013	$368

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Cash flows from operating activities:	'	'
Net income	$211,067	$73,059
Items not involving cash:	'	'
Stock-based compensation	19,724	13,161
Depreciation of property and equipment	28,204	12,945
Amortization of intangible assets	147,368	70,710
Deferred lease inducements and rent	24,042	1,409
Deferred income taxes	-36,225	-18,693
Tax benefit on stock-based compensation plans	-10,469	-17,214
Amortization of deferred financing fees	6,999	2,689
Changes in operating assets and liabilities, net of effects from acquisitions:	'	'
Accounts receivable	-119,630	-86,160
Rebates receivable	11,131	6,681
Restricted cash	199	9,338
Other current assets	8,036	29,494
Accounts payable	47,608	59,477
Accrued expenses and other current liabilities	-17,983	-24,459
Pharmacy benefit management rebates payable	14,022	10,336
Other	1,760	4,741
Net cash provided by operating activities	335,853	147,514
Cash flows from investing activities:	'	'
Proceeds from restricted cash	20,004	0
Acquisition, net of cash acquired	-7,076	-1,564,385
Purchases of property and equipment	-93,272	-12,901
Net cash used by investing activities	-80,344	-1,577,286
Cash flows from financing activities:	'	'
Proceeds from public offering, net of issuance costs	0	518,813
Proceeds from issuance of debt	100,000	1,470,448
Repayment of debt	-256,250	-511,993
Tax benefit on stock-based compensation plans	10,469	17,214
Proceeds from exercise of options and warrants	3,463	5,738
Payments of contingent consideration	-23,203	0
Debt issuance costs	-2,347	-18,806
Distribution to non-controlling interest	-22,115	0
Net cash (used) provided by financing activities	-189,983	1,481,414
Effect of foreign exchange on cash balances	-75	8
Increase in cash and cash equivalents	65,451	51,650
Cash and cash equivalents, beginning of period	370,776	341,382
Cash and cash equivalents, end of period	$436,227	$393,032

Consolidated_Statements_of_Equ

Consolidated Statements of Equity (USD $)	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income	Noncontrolling Interest
In Thousands, except Share data, unless otherwise specified
Total shareholders’ equity, beginning at Dec. 31, 2011	$671,038	$394,769	$37,936	$238,333	$0	$0
Common stock, shares, beginning at Dec. 31, 2011	'	124,767,322	'	'	'	'
Activities during the period (unaudited) [Roll Forward]	'	'	'	'	'	'
Net income attributable to the Company	74,129	'	'	74,129	'	'
Less: Net income (loss) attributable to non-controlling interest	-1,070	'	'	'	'	-1,070
Net income	73,059	'	'	'	'	'
Shares issued	'	11,960,000	'	'	'	'
Shares issued, amount	518,813	518,813	'	'	'	'
Issuance of common shares for acquisition, shares	'	66,779,940	'	'	'	'
Issuance of common shares for acquisition, value	3,238,144	3,238,144	'	'	'	'
Issuance of warrants and stock options for acquisition	19,824	'	19,824	'	'	'
Non-controlling interest assumed from acquisition	-1,610	'	'	'	'	-1,610
Exercise of stock options, shares	'	1,163,624	'	'	'	'
Exercise of stock options, amount	5,738	8,155	-2,417	'	'	'
Vesting of restricted stock units, shares	'	466,996	'	'	'	'
Vesting of restricted stock units, amount	0	17,923	-17,923	'	'	'
Tax benefit on options exercised	17,214	'	17,214	'	'	'
Stock-based compensation	13,161	'	13,161	'	'	'
Other comprehensive income, net of tax	-2,504	'	'	'	-2,504	'
Total shareholders’ equity, ending at Sep. 30, 2012	4,552,877	4,177,804	67,795	312,462	-2,504	-2,680
Common stock, shares, ending at Sep. 30, 2012	'	205,137,882	'	'	'	'
Total shareholders’ equity, beginning at Dec. 31, 2012	4,609,861	4,180,778	73,530	354,991	-2,191	2,753
Common stock, shares, beginning at Dec. 31, 2012	205,399,102	205,399,102	'	'	'	'
Activities during the period (unaudited) [Roll Forward]	'	'	'	'	'	'
Net income attributable to the Company	187,764	'	'	187,764	'	'
Less: Net income (loss) attributable to non-controlling interest	23,303	'	'	'	'	23,303
Net income	211,067	'	'	'	'	'
Exercise of stock options, shares	'	344,254	'	'	'	'
Exercise of stock options, amount	2,976	4,241	-1,265	'	'	'
Warrants exercised, shares	'	60,000	'	'	'	'
Warrants exercised, amount	487	2,910	-2,423	'	'	'
Vesting of restricted stock units, shares	'	494,964	'	'	'	'
Vesting of restricted stock units, amount	0	27,210	-27,210	'	'	'
Tax benefit on options exercised	10,469	'	10,469	'	'	'
Stock-based compensation	19,724	'	19,724	'	'	'
Distribution to non-controlling interest	-22,115	'	'	'	'	-22,115
Other comprehensive income, net of tax	194	'	'	'	194	'
Total shareholders’ equity, ending at Sep. 30, 2013	$4,832,663	$4,215,139	$72,825	$542,755	($1,997)	$3,941
Common stock, shares, ending at Sep. 30, 2013	206,298,320	206,298,320	'	'	'	'

Description_of_Business

Description of Business	9 Months Ended
	Sep. 30, 2013
Description of Business [Abstract]	'
Description of Business	'
	Description of Business
	Catamaran Corporation (“Catamaran” or the “Company”) is a leading provider of pharmacy benefits management (“PBM”) services and healthcare information technology (“HCIT”) solutions to the healthcare benefits management industry. The Company’s product offerings and solutions combine a wide range of PBM services, software applications, application service provider (“ASP”) processing services and professional services designed for many of the largest organizations in the pharmaceutical supply chain, such as federal, provincial, state and local governments, unions, corporations, pharmacy benefit managers, managed care organizations, retail pharmacy chains and other healthcare intermediaries. The Company is headquartered in Schaumburg, Illinois with several locations in the U.S. and Canada. The Company trades on the Toronto Stock Exchange under ticker symbol “CCT” and on the Nasdaq Global Select Market under ticker symbol “CTRX.”

Basis_of_Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2013
Basis of Presentation [Abstract]	'
Basis of Presentation	'
	Basis of Presentation
	Basis of presentation:
	The unaudited consolidated financial statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”), pursuant to the Securities and Exchange Commission’s (“SEC”) rules and regulations for reporting on Form 10-Q, and following accounting policies consistent with the Company’s audited annual consolidated financial statements for the year ended December 31, 2012. The unaudited consolidated financial statements of the Company include its wholly-owned subsidiaries and all significant intercompany transactions and balances have been eliminated in consolidation. Amounts in the unaudited consolidated financial statements and notes thereto are expressed in U.S. dollars, except where indicated. The financial information included herein reflects all adjustments (consisting only of normal recurring adjustments), which, in the opinion of management, are necessary for a fair presentation of the results for the periods presented. Certain reclassifications have been made to conform the prior year's consolidated financial statements to the current year's presentation. The results of operations for the three and nine month periods ended September 30, 2013 are not necessarily indicative of the results to be expected for the full year ending December 31, 2013. As of the issuance date of the Company’s financial statements, the Company has assessed whether subsequent events have occurred that require adjustment to or disclosure in these unaudited consolidated financial statements in accordance with Financial Accounting Standards Board’s (“FASB”) guidance.
	Pursuant to the SEC rules and regulations for reporting on Form 10-Q, certain information and note disclosures normally included in the annual consolidated financial statements prepared in accordance with GAAP have been condensed or excluded. As a result, these unaudited consolidated financial statements do not contain all the disclosures required to be included in the annual consolidated financial statements and should be read in conjunction with the most recent audited annual consolidated financial statements and notes thereto described in our Annual Report on Form 10-K for the year ended December 31, 2012.
	Use of estimates:
	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the period. Significant items subject to such estimates and assumptions include revenue recognition, rebates, purchase price allocation and contingent consideration in connection with acquisitions, valuation of property and equipment, valuation of intangible assets acquired and related amortization periods, impairment of goodwill, income tax uncertainties, contingencies and valuation allowances for receivables and income taxes. Actual results could differ from those estimates.

Recent_Accounting_Pronouncemen

Recent Accounting Pronouncements	9 Months Ended
	Sep. 30, 2013
Recent Accounting Pronouncements [Abstract]	'
Recent Accounting Pronouncements	'
	Recent Accounting Pronouncements
	a) Recent accounting standards implemented
	In February 2013, the FASB issued an update on the reporting of amounts reclassified from accumulated other comprehensive income. An entity is required to present either parenthetically on the face of the financial statements or in the notes, significant amounts reclassified from each component of accumulated other comprehensive income and the income statement line items affected by the reclassification. However, an entity would not need to show the income statement line item affected for certain components that are not required to be reclassified in their entirety to net income, such as amounts amortized into net periodic pension cost. The standard is effective prospectively for public entities for fiscal years, and interim periods with those years, beginning after December 15, 2012. The Company adopted this standard on January 1, 2013; however, the implementation of the amendments did not have a significant impact on its financial results or in the presentation and disclosure of its financial statements.
	No other new accounting standards have been adopted during the three and nine month periods ended September 30, 2013.
	b) Recent accounting standards issued
	In July 2013, the FASB issued authoritative guidance containing changes to the presentation of an unrecognized tax benefit when a loss or credit carryforward exists. The new standard requires the netting of unrecognized tax benefits against a deferred tax asset for a loss or other carryforward that would apply in the settlement of the uncertain tax positions. This statement is effective for financial statements issued for annual periods beginning after December 15, 2013, with early adoption permitted. Adoption of the standard is not expected to have a significant impact on the Company's financial results or in the presentation and disclosure of its financial statements.
	In July 2013, the FASB issued authoritative guidance allowing the inclusion of the Fed Funds Effective Swap Rate (or Overnight Index Swap Rate) as a benchmark interest rate for hedge accounting purposes in addition to the interest rates on direct Treasury obligations of the U.S. government and the London Interbank Offered Rate. The update also removes the restriction on using different benchmark rates for similar hedges. The new guidance can be applied by all companies that enter into hedging arrangements and is effective immediately. Adoption of the standard is not expected to have a significant impact on the Company's financial results or in the presentation and disclosure of its financial statements.
	No other new standards have been issued during the three and nine month periods ended September 30, 2013 that the Company assessed to have a significant impact on its financial results or in the presentation and disclosure of its financial statements.

Stock_Split

Stock Split	9 Months Ended
	Sep. 30, 2013
Equity [Abstract]	'
Stock Split	'
	Stock Split
	On September 6, 2012, the Company announced that its board of directors had declared a nominal dividend on the issued and outstanding common shares of the Company to effect a two-for-one stock split. Shareholders of record at the close of business on September 20, 2012 were issued one additional common share for each share owned as of that date. The additional common shares were distributed on October 1, 2012. All share and per share data presented in this report have been retroactively adjusted to reflect this stock split.

Business_Combinations

Business Combinations	9 Months Ended
	Sep. 30, 2013
Business Combinations [Abstract]	'
Business Combinations	'
	Business Combinations
	Catalyst Health Solutions, Inc. Merger
	On July 2, 2012, the Company completed its merger (the “Merger”) with Catalyst Health Solutions, Inc. ( "Catalyst"), a full-service PBM. Each share of Catalyst common stock outstanding immediately prior to the effective time of the Merger (other than shares owned by the Company or Catalyst or any of their respective wholly-owned subsidiaries) was converted in the Merger into the right to receive 1.3212 (0.6606 prior to the October 2012 two-for-one stock split) of a Company common share and $28.00 in cash. This resulted in the Company issuing approximately 66.8 million common shares, issuing 0.5 million warrants, and paying $1.4 billion in cash to Catalyst stockholders to complete the Merger. The results of Catalyst have been included in the Company's results since July 2, 2012. The consolidated statement of operations include total revenues from the Catalyst book of business of $1.9 billion and $5.3 billion, for the three and nine month periods ended September 30, 2013, respectively, and $1.5 billion for the three and nine month periods ended September 30, 2012.
	The Merger was accounted for under the acquisition method of accounting with the Company treated as the acquiring entity. Accordingly, the consideration paid by the Company to complete the acquisition has been allocated to the assets acquired and liabilities assumed based upon their estimated fair values as of the date of acquisition. The carrying values for current assets and liabilities were deemed to approximate their fair values due to the short-term nature of their maturities. The fair values for acquired customer relationships intangible asset was valued using an excess earnings model based on expected future revenues derived from the customers acquired. The excess of the purchase price over the estimated fair values of the net assets acquired was recorded as goodwill.
	All of the assets and liabilities recorded for the Merger are included within the Company's PBM segment. Goodwill is non-amortizing for financial statement purposes. Goodwill of $525 million related to the Catalyst Merger is tax deductible. The goodwill recognized by the Company represents many of the synergies and business growth opportunities that may be realized from this Merger. The synergies include improved pricing from the Company's suppliers due to the increased volume of prescription drug purchases, pull through opportunities of the combined companies' mail and specialty service offerings, and a more efficient leveraging of resources to achieve operating profits.
	The purchase price of the acquired Catalyst operations was comprised of the following (in thousands):
	Cash paid to Catalyst shareholders				$	1,415,276
	Fair value of common shares issued (a)				3,238,141
	Fair value of warrants and stock options issued (b)				19,824
	Total purchase price				$	4,673,241
	(a)	Valued based on the number of outstanding shares immediately prior to the Merger multiplied by the exchange ratio of 1.3212 (0.6606 prior to the October 2012 two-for-one stock split), multiplied by the closing market price of Catamaran shares on July 2, 2012.
	(b)	The Black-Scholes pricing model was used to calculate the fair value of the replacement warrants and stock options issued.
	The following summarizes the fair values assigned to the assets acquired and liabilities assumed at the acquisition date (in thousands):
		Initial Amounts Recognized at Acquisition Date (a)				Prior Measurement Period Adjustments (b)			Current Measurement Period Adjustments (c)			Current Amounts Recognized at Acquisition Date
	Cash and cash equivalents	$	93,775			$	(315	)	$	—		$	93,460
	Other current assets	695,888				5,202			2,411			703,501
	Total current assets	789,663				4,887			2,411			796,961
	Goodwill	4,010,235				8,492			16,141			4,034,868
	Customer relationships intangible	1,184,800				—			—			1,184,800
	Other long-term assets	87,174				1,547			8			88,729
	Total assets acquired	6,071,872				14,926			18,560			6,105,358
	Accounts Payable	338,819				—			5			338,824
	Pharmacy benefit management rebates payable	176,202				2,935			(1,522		)	177,615
	Accrued expenses and other current liabilities	187,851				1,348			5,473			194,672
	Long-term debt	311,994				—			—			311,994
	Other long-term liabilities	385,375				10,643			14,604			410,622
	Total liabilities assumed	1,400,241				14,926			18,560			1,433,727
	Non-controlling interest	(1,610		)		—			—			(1,610		)
	Net assets acquired	$	4,673,241			$	—		$	—		$	4,673,241
	(a) As previously reported in the Company's Form 10-Q for the period ended September 30, 2012.
	(b) These represent measurement period adjustments from the acquisition date through December 31, 2012 and were recorded to reflect changes in the estimated fair values of the associated assets acquired and liabilities assumed based on factors existing as of the acquisition date.
	(c) These represent measurement period adjustments during 2013 through the end of the measurement period and were recorded to reflect changes in the estimated fair values of the associated assets acquired and liabilities assumed based on factors existing as of the acquisition date.
	During the three and nine month periods ended September 30, 2013, the Company recognized $40.0 million and $126.0 million, respectively, of amortization expense from intangible assets acquired in the Catalyst Merger. Amortization associated with the Catalyst Merger for the remainder of 2013 is expected to be $40.0 million. The estimated fair value of the customer relationship intangible asset on the acquisition date was $1.2 billion with a useful life of 9 years. The intangible asset acquired will not have any residual value at the end of the amortization period. There were no in-process research and development assets acquired.
	HealthTran LLC Acquisition
	In January 2012, the Company completed the acquisition of all of the outstanding equity interests of HealthTran LLC (“HealthTran”), a full-service PBM, in exchange for $250 million in cash, subject to certain customary post-closing adjustments, in each case upon the terms and subject to the conditions contained in the HealthTran purchase agreement. HealthTran was an existing HCIT client and utilizes a Company platform for its claims adjudication services. The acquisition provides the opportunity to create new revenues from HealthTran's customer base and generate cost savings through purchasing and SG&A synergies. The results of HealthTran have been included in the Company's results since January 1, 2012.
	The HealthTran acquisition was accounted for under the acquisition method of accounting with the Company treated as the acquiring entity. Accordingly, the consideration paid by the Company to complete the acquisition has been allocated to the assets acquired and liabilities assumed based upon their estimated fair values as of the date of acquisition.
	The following summarizes the fair values assigned to the assets acquired and liabilities assumed at the acquisition date (in thousands):
		Initial Amounts Recognized at Acquisition Date (a)				Measurement Period Adjustments (b)			Current Amounts Recognized at Acquisition Date
	Current assets	$	30,654			$	245		$	30,899
	Property and equipment	2,787				—			2,787
	Goodwill	173,642				833			174,475
	Intangible assets	77,130				(2,600		)	74,530
	Total assets acquired	284,213				(1,522		)	282,691
	Current liabilities	36,784				(496		)	36,288
	Total liabilities assumed	36,784				(496		)	36,288
	Net assets acquired	$	247,429			$	(1,026	)	$	246,403
	(a) As previously reported in the Company's Form 10-Q for the period ended March 31, 2012.
	(b) These measurement period adjustments were recorded to reflect an additional $1.0 million paid to the former HealthTran owners for the working capital reconciliation and changes in the estimated fair values of the associated assets acquired and liabilities assumed based on factors existing as of the acquisition date.
	During the three and nine month periods ended September 30, 2013, the Company recognized $3.6 million and $10.9 million, respectively, of amortization expense from intangible assets acquired in the HealthTran acquisition. Amortization associated with the HealthTran acquisition for the remainder of 2013 is expected to be $3.6 million.
	The estimated fair values and useful lives of intangible assets acquired are as follows (dollars in thousands):
		Fair Value				Useful Life
	Trademarks/Trade names	$	1,750			6 months
	Customer relationships	69,800				4-9 years
	Non-compete agreements	2,600				5 years
	License	380				3 years
	Total	$	74,530
	None of the acquired intangible assets will have any residual value at the end of the amortization periods. There were no in-process research and development assets acquired.
	Unaudited Pro Forma Financial Information
	The following unaudited pro forma financial information presents the combined historical results of operations of the Company and Catalyst as if the Merger had occurred on January 1, 2012. The unaudited pro forma financial information includes certain adjustments related to the acquisitions, such as increased amortization from the fair value of intangible assets acquired, income tax effects related to the acquisition and the elimination of transactions between the Company and Catalyst. Unaudited pro forma results of operations are as follows (in thousands, except share and per share amounts):
		Nine Months Ended September 30, 2012
	Revenue	$	9,609,135
	Gross profit	$	654,852
	Net income	$	79,424
Earnings per share:
Basic	$	0.39
Diluted	$	0.39
Weighted average shares outstanding:
Basic	204,350,003
Diluted	205,477,142
This unaudited pro forma financial information is not intended to represent or be indicative of what would have occurred if these transactions had taken place on the date presented and is not indicative of what the Company's actual results of operations would have been had the acquisitions been completed at the beginning of the period indicated above. Further, the pro forma combined results do not reflect one-time costs to fully integrate and operate the combined organization more efficiently or anticipated synergies expected to result from the combinations and should not be relied upon as being indicative of the future results that the Company will experience.
Restat, LLC Acquisition
On October 1, 2013, the Company completed the previously announced acquisition of Restat, LLC, a privately held pharmacy benefit manager based in Milwaukee, Wisconsin, for a purchase price of $409.5 million in cash subject to certain customary post-closing adjustments. The purchase price was funded from Catamaran’s existing cash balance and $350 million in borrowings under its Revolving Facility.
The acquisition provides the Company the opportunity to bring Catamaran's full suite of technology and clinical services to Restat's clients, including mail order and specialty pharmacy services. The initial accounting for this acquisition was incomplete at the time these financial statements were available for issuance. The Company expects to finalize the accounting for the acquisition as soon as practicable, but no later than one year from the acquisition closing date.

Goodwill_and_Other_Intangible_

Goodwill and Other Intangible Assets	9 Months Ended
	Sep. 30, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'
Goodwill and Other Intangible Assets	'
	Goodwill and Other Intangible Assets
	Goodwill is reviewed for impairment annually or more frequently if impairment indicators arise. The Company allocates goodwill to both the PBM and HCIT segments. There were no impairments of goodwill during the three and nine months ended September 30, 2013 and 2012.
	The changes in the carrying amounts of goodwill by reportable segment for the nine months ended September 30, 2013 are as follows (in thousands):
		PBM		HCIT			Total
	Balance at December 31, 2012	4,458,373		19,665			4,478,038
	Measurement period adjustments (a)	16,472		—			16,472
	Acquisitions	3,111		—			3,111
	Balance at September 30, 2013	4,477,956		19,665			4,497,621
	a)	Adjustments to the fair value of assets acquired and liabilities assumed for recent acquisitions during the measurement period. The measurement period adjustments were not recast to the 2012 consolidated financial statements as they were not deemed material.
	Definite-lived intangible assets are amortized over the useful lives of the related assets. The components of intangible assets were as follows (in thousands):
		September 30, 2013								December 31, 2012
		Gross Carrying Amount			Accumulated Amortization			Net		Gross Carrying Amount		Accumulated Amortization		Net
	Customer relationships	$	1,349,774		$	300,899		$	1,048,875	$	1,346,874	$	155,343	$	1,191,531
	Acquired software	—			—			—		3,765		3,765		—
	Trademarks/Tradenames	—			—			—		14,070		14,070		—
	Non-compete agreements	10,410			5,821			4,589		10,410		4,294		6,116
	Licenses	2,060			1,001			1,059		2,060		716		1,344
	Total	$	1,362,244		$	307,721		$	1,054,523	$	1,377,179	$	178,188	$	1,198,991
	Total amortization associated with intangible assets at September 30, 2013 is estimated to be $47.1 million for the remainder of 2013, $179.5 million in 2014, $164.4 million in 2015, $142.9 million in 2016, $131.5 million in 2017, $122.4 million in 2018 and $266.7 million in total for years 2019 through 2023.

Debt

Debt	9 Months Ended
	Sep. 30, 2013
Debt Disclosure [Abstract]	'
Debt	'
	Debt
	The following table sets forth the components of our long-term debt (in thousands) as of September 30, 2013 and December 31, 2012.
		30-Sep-13			31-Dec-12
	Senior secured term loan facility with an interest rate of 1.81% and 2.25% at September 30, 2013 and December 31, 2012, respectively	$	970,360		$	1,073,403
	Senior secured revolving credit facility due June 1, 2018 with an interest rate of 1.81% and 2.25% at September 30, 2013 and December 31, 2012, respectively	50,000			100,000
	Less current maturities	(43,750		)	(41,250		)
	Long-term debt	$	976,610		$	1,132,153
	On June 3, 2013, the Company entered into an Amendment (the “Amendment”) to the Credit Agreement dated July 2, 2012 (the "Credit Agreement"), with JPMorgan Chase Bank, N.A. ("JPMCB"), as administrative agent, and a syndicate of lenders. The Credit Agreement initially provided for a senior secured credit facility in an aggregate amount of $1.8 billion consisting of (i) a five-year senior secured term loan facility in the amount of $1.1 billion (the “Term Loan Facility”) and (ii) a five-year senior secured revolving credit facility in the amount of $700 million (the “Revolving Facility”).
	Pursuant to the Amendment, the following key terms of the Credit Agreement were modified:
	•	an extension of the maturity date for the Term Loan Facility and the Revolving Facility from July 2, 2017 to June 1, 2018;
	•	an increase in the commitments under the Revolving Facility from $700 million to $800 million;
	•	a decrease in the commitments under the Term Loan Facility from $1.1 billion to $1.0 billion;
	•	additional flexibility for the Company and its subsidiaries to (i) make certain permitted acquisitions, (ii) create liens, (iii) make investments, loans, advances or guarantees, and (iv) pay dividends and distributions or repurchase its own capital stock; and
	•	modifications to the interest rates and financial covenants applicable to the Company and its subsidiaries as described further below.
	After giving effect to the Amendment, the interest rates applicable to the Term Loan Facility and the Revolving Facility will continue to be based on a fluctuating rate of interest measured by reference to either, at the Company's option, (i) a base rate, plus an applicable margin, or (ii) an adjusted London interbank offered rate (adjusted for maximum reserves) (“LIBOR”), plus an applicable margin. The applicable margin, in each case, will continue to be adjusted from time to time based on the Company's consolidated leverage ratio for the previous fiscal quarter. The Amendment provides for a reduction in the applicable margins that would be in effect at any time when the Company's consolidated leverage ratio is greater than 1.50 to 1 and less than 2.50 to 1. After giving effect to the Amendment, the initial applicable margin for all borrowings is 0.625% per annum with respect to base rate borrowings and 1.625% per annum with respect to LIBOR borrowings. The Company intends to continue to elect the LIBOR rate as it has previously done during the term of the loan. This resulted in the applicable interest rate decreasing to 1.81% at September 30, 2013 from 2.25% prior to the Amendment. See Note 12 — Financial Instruments for information on the Company's interest rate swap agreements.
	In connection with the Amendment, the Company made a $100 million prepayment on the Term Loan Facility to reduce its outstanding balance to $1.0 billion from $1.1 billion. The Company utilized funds from its Revolving Facility to make the prepayment, leaving the Company with $700 million of remaining available borrowing capacity under the Revolving Facility at the time of the Amendment execution. In June 2013, the Company repaid $50 million of the amount borrowed under the Revolving Facility, leaving the Company with $750 million of borrowing capacity under the Revolving Facility as of September 30, 2013. On October 1, 2013, the Company utilized $350 million under the Revolving Facility to partially fund the acquisition of Restat. The Company made a principal repayment of $6.3 million in July 2013 on the Term Loan facility leaving the Company with $993.8 million outstanding as of September 30, 2013. In connection with executing the Amendment, the Company paid $2.3 million in direct lender fees to the syndication of banks providing credit to the Company. The fees consisted of a $1.3 million debt discount related to the Term Loan Facility and $1.0 million of debt issuance costs related to the Revolving Facility. The $1.3 million debt discount incurred in connection with the Amendment is presented on the consolidated balance sheet as a reduction to long-term debt, along with the $24.1 million of unamortized debt discount incurred in connection with the execution of the Credit Agreement. The debt discount amounts are being amortized to interest expense over the amended life of the Term Loan Facility. The Company uses the straight-line method to amortize the debt discount as it does not result in a materially different amount of interest expense than the effective interest rate method. The additional $1.0 million debt issue cost incurred in connection with the execution of the Amendment related to the Revolving Facility, along with $16.6 million of unamortized debt issuance costs incurred in connection with the execution of the Credit Agreement, are presented on the consolidated balance sheet as other assets. The debt issuance costs are being amortized to interest expense over the amended life of the Revolving Facility using the straight-line method. The amortization related to financing costs and debt discounts totaled $2.1 million and $7.0 million for the three and nine month periods ended September 30, 2013, respectively.
	Upon executing the Amendment, the Company assessed whether the modifications to the Credit Agreement were substantial and should be accounted for using extinguishment accounting. The Company made its assessment both on a total basis and on an individual basis for each member of the syndication. The Company performed separate assessments for the Term Loan Facility and the Revolving Facility. As a result of the assessments, the Company recorded an additional interest expense charge of $0.4 million from unamortized debt discount and debt issuance costs during the nine months ended September 30, 2013.
	As previously disclosed, the Credit Agreement prior to giving effect to the Amendment required the Company to maintain a consolidated leverage ratio at all times less than or equal to 3.75 to 1 initially, with step-downs to (i) 3.50 to 1 beginning with the fiscal quarter ending December 31, 2012, (ii) 3.25 to 1 beginning with the fiscal quarter ending December 31, 2013 and (iii) 3.00 to 1 beginning with the fiscal quarter ending December 31, 2014. The Credit Agreement, as amended by the Amendment, requires the Company to maintain a consolidated leverage ratio at all times less than or equal to 4.00 to 1 and a consolidated senior secured leverage ratio at all times less than or equal to 3.25 to 1. As previously disclosed, the Company's consolidated leverage ratio is defined as the ratio of (1) consolidated total debt to (2) consolidated EBITDA (with add-backs permitted to consolidated EBITDA for (a) fees and expenses related to the Merger, the closing of the Credit Agreement, a specified historic acquisition and future permitted acquisitions, (b) synergies projected by the Company in good faith to be realized as a result of the Merger in an aggregate amount not to exceed a specified threshold and (c) fees and expenses and integration costs related to historical acquisitions by Catalyst in an aggregate amount not to exceed a specified threshold). The Company's new consolidated senior secured leverage ratio is defined as the ratio of (1) (a) consolidated total debt minus (b) any portion of consolidated total debt that is subordinated or not secured by a lien upon the assets of the Company or its subsidiaries to (2) consolidated EBITDA (subject to the permitted add-backs noted above). The Credit Agreement, as amended by the Amendment, continues to require the Company to maintain an interest coverage ratio greater than or equal to 4.00 to 1. As previously disclosed, the interest coverage ratio is defined as the ratio of (1) consolidated EBIT (subject to the permitted add-backs noted above) to (2) consolidated interest expense, tested at the end of each fiscal quarter for the rolling four fiscal quarter period then most recently ended. As of September 30, 2013, the Company was in compliance with the covenants of the Credit Agreement, as amended by the Amendment.
	Principal amounts outstanding under the Revolving Facility of the Amendment are due and payable in full on June 1, 2018. Principal repayments on the Term Loan Facility will be due as follows (in thousands):
	Year	Amount due
	2013	$	12,500
	2014	43,750
	2015	68,750
	2016	93,750
	2017	118,750
	2018	656,250
	Total	$	993,750
	The Credit Agreement also contains a number of covenants that, among other things, restrict, subject to certain exceptions, the ability of the Company and its subsidiaries to: incur additional indebtedness; create liens; make investments, loans, advances or guarantees; sell or transfer assets; pay dividends and distributions or repurchase its own capital stock; prepay certain indebtedness; engage in mergers, acquisitions or consolidations (subject to exceptions for certain permitted acquisitions); change its lines of business or enter into new lines of business; engage in certain transactions with affiliates; enter into agreements restricting the ability to grant liens in favor of the collateral agent for the benefit of the secured parties; engage in sale and leaseback transactions; or enter into swap, forward, future or derivative transaction or option or similar agreements. In addition, the Credit Agreement includes various (i) customary affirmative covenants and other reporting requirements and (ii) customary events of default, including, without limitation, payment defaults, violation of covenants, material inaccuracy of representations or warranties, cross-defaults to other material agreements evidencing indebtedness, bankruptcy events, certain ERISA events, material judgments, invalidity of guarantees or security documents and change of control. Drawings under the Revolving Facility are subject to certain conditions precedent, including material accuracy of representations and warranties and absence of default.
	The Company’s obligations under the Credit Agreement are guaranteed by all existing and future, direct and indirect, material subsidiaries of the Company (collectively, the “Subsidiary Guarantors”).  In addition, the Company and each Subsidiary Guarantor have pledged substantially all of their assets, subject to certain exceptions, to secure the Company’s obligations under the Credit Agreement.
	The carrying value of the Company's debt at September 30, 2013 approximates its fair value.

Common_Shares_and_StockBased_C

Common Shares and Stock-Based Compensation	9 Months Ended
	Sep. 30, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Common Shares and Stock-Based Compensation	'
	Common Shares and Stock-Based Compensation
	(a) Issuance of common shares
	On May 16, 2012, the Company completed a public offering of 12.0 million of its common shares at a price to the public of $45.30 per share. The net proceeds to the Company from the offering were approximately $519.1 million, after deducting the underwriting discounts and commissions and offering expenses. The Company used part of the net proceeds from the offering to pay a portion of the cash component of the Merger consideration and other related fees and expenses in connection with the Merger and the balance for general corporate purposes.
	On July 2, 2012, the Company issued 66.8 million common shares and 0.5 million warrants in connection with the Catalyst Merger. See Note 5 — Business Combinations for further information related to the Merger.
	(b) Equity incentive plans
	In July 2012, the maximum common shares of the Company allowed to be issued under the Catamaran Corporation Long-Term Incentive Plan (“LTIP”) was increased by 5 million, after the Company's shareholders approved an amendment to the LTIP at a Special Meeting of Shareholders of the Company on July 2, 2012.
	In connection with the closing of the Merger with Catalyst on July 2, 2012, the Company assumed two stock incentive plans (together the "Assumed Plans") each as amended and adjusted for the purpose of granting awards to individuals who became employees of the Company subsequent to the close of the Merger or to newly hired employees of the Company who were not employed with the Company as of the close of the Merger. The maximum common shares of the Company allowed to be issued under the Assumed Plans is 1,480,936.
	(c) Stock-based compensation
	During the three-month periods ended September 30, 2013 and 2012, the Company recorded stock-based compensation expense of $6.6 million and $6.3 million, respectively. During the nine months ended September 30, 2013 and 2012 the Company recorded stock-based compensation expense of $19.7 million and $13.2 million, respectively. There were 6,867,399 and 1,053,891 stock-based awards available for grant under the LTIP and the Assumed Plans, respectively, as of September 30, 2013.
	(i) Stock options
	The Black-Scholes option-pricing model was used to estimate the fair value of the stock options issued in each period at the grant date. Below is a summary of options granted and the assumptions utilized to derive fair value of the stock options under the Black-Scholes option-pricing model:
		Nine Months Ended September 30,
		2013			2012
	Total stock options granted	367,195			404,652
	Volatility	41.8% - 45.4%			47.2% - 49.2%
	Risk-free interest rate	0.81% - 1.74%			0.65% - 0.83%
	Expected life (in years)	4.5			4.5
	Dividend yield	—			—
	Weighted-average grant date fair value	$	21.44		$	29.4
	The table below summarizes the stock options outstanding as of September 30, 2013 under both plans.
			Options Outstanding		Weighted Average Exercise Price				Unrecognized compensation cost			Weighted Average Period
									(in thousands)
	LTIP Plan
	Canadian Options		3,064		$	3.35
	U.S.Options		1,373,474		$	30.84			$	10,140		2.72
	Assumed Plans
	U.S.Options		49,665		$	56.21			$	876		$	3.45
	(ii) Restricted stock units
	During the three and nine months ended September 30, 2013, the Company granted time-based RSUs and performance-based RSUs to its employees and non-employee directors under both the LTIP and the Assumed Plans. Time-based RSUs vest on a straight-line basis over a range of two to four years. The Company also granted time-based RSUs that cliff vest after a three to four year period. Performance-based RSUs cliff vest based upon reaching agreed upon three-year performance conditions. The number of outstanding performance-based RSUs as of September 30, 2013 stated below assumes the associated performance targets will be met at the maximum level.
	The table below summarizes the number of time-based and performance-based RSUs that were granted and outstanding under both plans for the nine months ended September 30, 2013:
		LTIP Plan									Assumed Plans
		Number of Restricted Stock Units									Number of Restricted Stock Units
		Time-Based		Performance - Based			Weighted Average Grant Date Fair Value Per Unit				Time-Based		Performance - Based	Weighted Average Grant Date Fair Value Per Unit
	Granted	251,970		253,980			$	56.25			130,320		25,570	$	55.78
	Outstanding	702,978		674,496							205,830		17,510
	The table below summarizes the unrecognized compensation cost related to the outstanding RSUs at September 30, 2013.
		Unrecognized Compensation Cost			Weighted Average Period
		(in thousands)
	LTIP	$	35,200		2.37
	Assumed Plans	$	9,832		3.16

Segment_Information

Segment Information	9 Months Ended
	Sep. 30, 2013
Segment Reporting [Abstract]	'
Segment Information	'
	Segment Information
	The Company reports in two operating segments: PBM and HCIT. The Company evaluates segment performance based upon revenue and gross profit. Financial information by segment is presented below (in thousands):
		Three Months Ended September 30,				Nine Months Ended September 30,
		2013		2012		2013		2012
	PBM:
	Revenue	$	3,578,767	$	3,150,755	$	10,142,515	$	6,493,029
	Cost of revenue	3,310,636		2,940,060		9,399,949		6,094,664
	Gross profit	$	268,131	$	210,695	$	742,566	$	398,365
	Total assets at September 30	$	7,115,563	$	7,146,899	$	7,115,563	$	7,146,899
	HCIT:
	Revenue	$	35,381	$	40,025	$	108,780	$	117,551
	Cost of revenue	15,724		15,829		50,597		48,132
	Gross profit	$	19,657	$	24,196	$	58,183	$	69,419
	Total assets at September 30	$	377,323	$	226,309	$	377,323	$	226,309
	Consolidated:
	Revenue	$	3,614,148	$	3,190,780	$	10,251,295	$	6,610,580
	Cost of revenue	3,326,360		2,955,889		9,450,546		6,142,796
	Gross profit	$	287,788	$	234,891	$	800,749	$	467,784
	Total assets at September 30	$	7,492,886	$	7,373,208	$	7,492,886	$	7,373,208

Income_Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2013
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	Income Taxes
	The Company’s effective tax rate for the three months ended September 30, 2013 and 2012 was 25.2% and 39.8%, respectively. The Company’s effective tax rate for the nine months ended September 30, 2013 and 2012 was 26.4% and 37.2%, respectively. The Company and its subsidiaries file income tax returns in the U.S. federal jurisdiction, and various state and foreign jurisdictions including Canada. With a few exceptions, the Company is no longer subject to tax examinations by tax authorities for years prior to 2007. The Company's effective tax rate decreased during the three and nine months ended September 30, 2013 primarily due to tax benefits related to cross-jurisdictional financing as well as expenses incurred during the three and nine months ended September 30, 2012 related to the Merger that were not tax deductible.

Commitments_and_Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2013
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	Commitments and Contingencies
	From time to time in connection with its operations, the Company is named as a defendant in actions for damages and costs allegedly sustained by third party plaintiffs. The Company has considered these proceedings and disputes in determining the necessity of any accruals for losses that are probable and reasonably estimable. In addition, various aspects of the Company’s business may subject it to litigation and liability for damages arising from errors in processing the pricing of prescription drug claims, failure to meet performance measures within certain contracts relating to its services performed, its ability to obtain certain levels of discounts or rebates on prescription purchases from retail pharmacies and drug manufacturers or other actions or omissions. The Company’s recorded accruals are based on estimates developed with consideration given to the potential merits of claims or quantification of any performance obligations. The Company takes into account its history of claims, the limitations of any insurance coverage, advice from outside counsel, and management’s strategy with regard to the settlement or defense of such claims and obligations. While the ultimate outcome of those claims, lawsuits or performance obligations cannot be predicted with certainty, the Company believes, based on its understanding of the facts of these claims and performance obligations, that adequate provisions have been recorded in the accounts where required.

Financial_Instruments

Financial Instruments	9 Months Ended
	Sep. 30, 2013
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Financial Instruments	'
	Financial Instruments
	The Company used variable rate debt to partially finance its Merger with Catalyst. The Company is subject to interest rate risk related to the variable rate debt. When interest rates increase, interest expense would increase. Conversely, when interest rates decrease, interest expense would also decrease.
	In order to manage fluctuations in cash flows resulting from interest rate risk attributable to changes in the benchmark interest rates, in September 2012 the Company entered into 3-year interest rate swap agreements with a total notional amount of $500 million to fix the variable LIBOR rate on the Company's Term Loan Facility to 0.52%, resulting in a current effective rate of 2.14% after taking into account the 1.625% margin per the Credit Agreement, as amended. Under the interest rate swap, the Company receives LIBOR-based variable interest rate payments and makes fixed interest rate payments, thereby creating the equivalent to fixed-rate debt with respect to the notional amount of such swap agreements. These interest rate contract derivative instruments were designated as cash flow hedges upon inception in September 2012.
	The Company assesses interest rate cash flow risk by continually identifying and monitoring changes in interest rate exposures that may adversely impact expected future cash flows and by evaluating hedging opportunities. The Company does not enter into derivative instruments for any purpose other than hedging identified exposures. That is, the Company does not speculate using derivative instruments and has not designated any instruments as fair value hedges or hedges of the foreign currency exposure of a net investment in foreign operations.
	The fair value of the interest rate swap liability as of September 30, 2013 was $1.8 million. Interest expense for the three and nine months ended September 30, 2013 includes $0.4 million and $1.1 million, respectively, of expense reclassified from other comprehensive income into current earnings. As of September 30, 2013, approximately $1.7 million of deferred expenses related to the derivative instruments accumulated in other comprehensive income is expected to be reclassified as interest expense during the next twelve months. This expectation is based on the expected timing of the occurrence of the hedged forecasted transactions and assumes the current LIBOR rate will remain consistent. Fluctuations in the market LIBOR rate will have an impact on the amount of expense reclassified from accumulated other comprehensive income to interest expense, as well as the overall fair value of the derivative instrument.

Fair_Value

Fair Value	9 Months Ended
	Sep. 30, 2013
Fair Value Disclosures [Abstract]	'
Fair Value	'
	Fair Value
	Fair value measurement guidance defines a three-level hierarchy to prioritize the inputs to valuation techniques used to measure fair value into three broad levels, with Level 1 considered the most reliable. During the three and nine month periods ended September 30, 2013, there were no movements of fair value measurements between Levels 1, 2 and 3. For assets and liabilities measured at fair value on a recurring basis in the consolidated balance sheets, the table below categorizes fair value measurements across the three levels as of September 30, 2013 and December 31, 2012 (in thousands):
		September 30, 2013
		Quoted Prices in Active Markets (Level 1)		Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
	Liabilities:
	Contingent purchase price consideration	$	—	$	—	$	19,840	$	19,840
	Derivative	$	—	$	1,751	$	—	$	1,751
		December 31, 2012
		Quoted Prices in Active Markets (Level 1)		Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
	Liabilities:
	Contingent purchase price consideration	$	—	$	—	$	49,183	$	49,183
	Derivative	$	—	$	2,639	$	—	$	2,639
	When available and appropriate, the Company uses quoted market prices in active markets to determine fair value, and classifies such items within Level 1. Level 1 values only include instruments traded on a public exchange. Level 2 inputs are inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the financial instrument. Level 2 inputs include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, or inputs other than quoted prices that are observable for the asset or liability or can be derived principally from or corroborated by observable market data. If the Company were to use one or more significant unobservable inputs for a model-derived valuation, the resulting valuation would be classified in Level 3.
	Contingent purchase price consideration
	The contingent purchase price consideration liability reflects the fair values of potential future payments related to certain legacy acquisitions. The potential future payments are contingent upon the acquired entities meeting certain revenue, gross margin and client retention milestones through March 31, 2014. As of September 30, 2013, the fair value of the contingent purchase price consideration was $19.8 million and was recorded as accrued expenses and other current liabilities in the consolidated balance sheet. The contingent purchase price consideration decreased for the three and nine months ended September 30, 2013 as compared to the fair value reported for the year ended December 31, 2012 due to payments of $25.5 million and an adjustment of $4.5 million which was recognized in SG&A in the consolidated statement of operations.
	The change in the present value of the amount expected to be paid in the future for the contingent purchase price consideration was $0.1 million and $0.5 million for the three and nine months ended September 30, 2013, respectively, and was recorded as interest expense in the consolidated statement of operations. The Company utilized a probability weighted discounted cash flow method to arrive at the fair value of the contingent consideration based on the expected results or the achievement of client retention milestones.
	As the fair value measurement for the contingent consideration is based on inputs not observed in the market, these measurements are classified as Level 3 measurements as defined by fair value measurements guidance.
	Derivatives
	Derivative liabilities relate to the interest rate swap agreements (refer to Note 12 — Financial Instruments for further information), which had a fair value of $1.8 million as of September 30, 2013. As the fair value measurement for the derivative instruments are based on quoted prices from a financial institution, these measurements are classified as Level 2 measurements as defined by fair value measurements guidance.

Lease_Exit_Costs

Lease Exit Costs	9 Months Ended
	Sep. 30, 2013
Leases [Abstract]	'
Lease Exit Costs	'
	Lease Exit Costs
	In August 2013, the Company executed a plan to exit a portion of space it had leased in Maryland and entered into a sub-lease agreement with a third-party tenant that was coterminous with the Company's remaining lease term. As a result of this exit, the Company recorded a charge and corresponding lease loss accrual equal to the present value of the amount by which the net future lease obligations exceed the remaining rent-related deferred balances. The net future lease obligations were calculated by taking the remaining contractual rent obligation less the amount the Company will receive from the sub-lease agreement and recorded at its present value based on the Company's credit adjusted risk-free interest rate. During the three and nine month periods ended September 30, 2013, the Company recorded approximately $5.6 million of lease loss expense as a result of this exit in SG&A expense in the consolidated statements of operations.
	As of September 30, 2013, the Company had a lease loss accrual of approximately $5.6 million, which is included in accrued expenses and other current liabilities in the consolidated balance sheets. Remaining lease payments, and remaining sub-lease receipts, associated with the Maryland lease loss accrual are expected to be paid and received over the remaining lease term. Based on the Company's current assumptions as of September 30, 2013, expected lease payments, net of sub-lease receipts, are expected to result in a total net cash outlay of approximately $7.2 million for the remaining lease term. The partial exit from the space in Maryland did not involve any employee termination costs or trigger any material asset impairment charges.

Earnings_Per_Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	Earnings Per Share
	The Company calculates basic EPS using the weighted average number of common shares outstanding during the period. Diluted EPS is calculated using the same method as basic EPS, but the Company adds the number of additional common shares that would have been outstanding for the period if the potential dilutive common shares had been issued. The following is the reconciliation between the number of weighted average shares used in the basic and diluted EPS calculations for the three and nine month periods ended September 30, 2013 and 2012:
		Three Months Ended September 30,		Nine Months Ended September 30,
		2013	2012	2013	2012
	Weighted average number of shares used in computing basic EPS	206,203,263	203,505,355	205,920,803	153,850,043
	Add dilutive common stock equivalents:
	Outstanding stock options and restricted stock units (a)	621,355	933,693	716,120	1,127,139
	Weighted average number of shares used in computing diluted EPS	206,824,618	204,439,048	206,636,923	154,977,182
	(a) Excludes 746,691 and 1,212,910 common stock equivalents for the three-month periods ended September 30, 2013 and 2012 because their effect was anti-dilutive. Excludes 633,407 and 1,021,501 common stock equivalents for the nine-month periods ended September 30, 2013 and 2012 because their effect was anti-dilutive.

Concentration_Risk

Concentration Risk	9 Months Ended
	Sep. 30, 2013
Risks and Uncertainties [Abstract]	'
Concentration Risk	'
	Concentration Risk
	For the three month periods ended September 30, 2013 and 2012, one client accounted for 19% and 24% of total revenues, respectively. For the nine-month period ended September 30, 2013 and 2012, one client accounted for 19% and 35% of total revenues, respectively.
	At September 30, 2013, one client accounted for 10% of the outstanding accounts receivable balance. At December 31, 2012, one client accounted for 13% of the outstanding accounts receivable balance and a separate client accounted for 12% of the outstanding receivable balance.

Basis_of_Presentation_Policies

Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2013
Basis of Presentation [Abstract]	'
Consolidation	'
	Basis of presentation:
	The unaudited consolidated financial statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”), pursuant to the Securities and Exchange Commission’s (“SEC”) rules and regulations for reporting on Form 10-Q, and following accounting policies consistent with the Company’s audited annual consolidated financial statements for the year ended December 31, 2012. The unaudited consolidated financial statements of the Company include its wholly-owned subsidiaries and all significant intercompany transactions and balances have been eliminated in consolidation. Amounts in the unaudited consolidated financial statements and notes thereto are expressed in U.S. dollars, except where indicated. The financial information included herein reflects all adjustments (consisting only of normal recurring adjustments), which, in the opinion of management, are necessary for a fair presentation of the results for the periods presented. Certain reclassifications have been made to conform the prior year's consolidated financial statements to the current year's presentation. The results of operations for the three and nine month periods ended September 30, 2013 are not necessarily indicative of the results to be expected for the full year ending December 31, 2013. As of the issuance date of the Company’s financial statements, the Company has assessed whether subsequent events have occurred that require adjustment to or disclosure in these unaudited consolidated financial statements in accordance with Financial Accounting Standards Board’s (“FASB”) guidance.
	Pursuant to the SEC rules and regulations for reporting on Form 10-Q, certain information and note disclosures normally included in the annual consolidated financial statements prepared in accordance with GAAP have been condensed or excluded. As a result, these unaudited consolidated financial statements do not contain all the disclosures required to be included in the annual consolidated financial statements and should be read in conjunction with the most recent audited annual consolidated financial statements and notes thereto described in our Annual Report on Form 10-K for the year ended December 31, 2012.
Use of Estimates	'
	Use of estimates:
	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the period. Significant items subject to such estimates and assumptions include revenue recognition, rebates, purchase price allocation and contingent consideration in connection with acquisitions, valuation of property and equipment, valuation of intangible assets acquired and related amortization periods, impairment of goodwill, income tax uncertainties, contingencies and valuation allowances for receivables and income taxes. Actual results could differ from those estimates.

Business_Combinations_Tables

Business Combinations (Tables)	9 Months Ended
	Sep. 30, 2013
Business Acquisition [Line Items]	'
Unaudited pro forma results of operations	'
	Unaudited pro forma results of operations are as follows (in thousands, except share and per share amounts):
		Nine Months Ended September 30, 2012
	Revenue	$	9,609,135
	Gross profit	$	654,852
	Net income	$	79,424
	Earnings per share:
	Basic	$	0.39
	Diluted	$	0.39
	Weighted average shares outstanding:
	Basic	204,350,003
	Diluted	205,477,142
Catalyst	'
Business Acquisition [Line Items]	'
Schedule of total purchase price	'
	The purchase price of the acquired Catalyst operations was comprised of the following (in thousands):
	Cash paid to Catalyst shareholders				$	1,415,276
	Fair value of common shares issued (a)				3,238,141
	Fair value of warrants and stock options issued (b)				19,824
	Total purchase price				$	4,673,241
	(a)	Valued based on the number of outstanding shares immediately prior to the Merger multiplied by the exchange ratio of 1.3212 (0.6606 prior to the October 2012 two-for-one stock split), multiplied by the closing market price of Catamaran shares on July 2, 2012.
	(b)	The Black-Scholes pricing model was used to calculate the fair value of the replacement warrants and stock options issued.
Schedule of fair values assigned to assets acquired and liabilities assumed at the acquisition date	'
	The following summarizes the fair values assigned to the assets acquired and liabilities assumed at the acquisition date (in thousands):
		Initial Amounts Recognized at Acquisition Date (a)				Prior Measurement Period Adjustments (b)			Current Measurement Period Adjustments (c)			Current Amounts Recognized at Acquisition Date
	Cash and cash equivalents	$	93,775			$	(315	)	$	—		$	93,460
	Other current assets	695,888				5,202			2,411			703,501
	Total current assets	789,663				4,887			2,411			796,961
	Goodwill	4,010,235				8,492			16,141			4,034,868
	Customer relationships intangible	1,184,800				—			—			1,184,800
	Other long-term assets	87,174				1,547			8			88,729
	Total assets acquired	6,071,872				14,926			18,560			6,105,358
	Accounts Payable	338,819				—			5			338,824
	Pharmacy benefit management rebates payable	176,202				2,935			(1,522		)	177,615
	Accrued expenses and other current liabilities	187,851				1,348			5,473			194,672
	Long-term debt	311,994				—			—			311,994
	Other long-term liabilities	385,375				10,643			14,604			410,622
	Total liabilities assumed	1,400,241				14,926			18,560			1,433,727
	Non-controlling interest	(1,610		)		—			—			(1,610		)
	Net assets acquired	$	4,673,241			$	—		$	—		$	4,673,241
	(a) As previously reported in the Company's Form 10-Q for the period ended September 30, 2012.
	(b) These represent measurement period adjustments from the acquisition date through December 31, 2012 and were recorded to reflect changes in the estimated fair values of the associated assets acquired and liabilities assumed based on factors existing as of the acquisition date.
	(c) These represent measurement period adjustments during 2013 through the end of the measurement period and were recorded to reflect changes in the estimated fair values of the associated assets acquired and liabilities assumed based on factors existing as of the acquisition date.
HealthTran	'
Business Acquisition [Line Items]	'
Schedule of fair values assigned to assets acquired and liabilities assumed at the acquisition date	'
	The following summarizes the fair values assigned to the assets acquired and liabilities assumed at the acquisition date (in thousands):
		Initial Amounts Recognized at Acquisition Date (a)				Measurement Period Adjustments (b)			Current Amounts Recognized at Acquisition Date
	Current assets	$	30,654			$	245		$	30,899
	Property and equipment	2,787				—			2,787
	Goodwill	173,642				833			174,475
	Intangible assets	77,130				(2,600		)	74,530
	Total assets acquired	284,213				(1,522		)	282,691
	Current liabilities	36,784				(496		)	36,288
	Total liabilities assumed	36,784				(496		)	36,288
	Net assets acquired	$	247,429			$	(1,026	)	$	246,403
	(a) As previously reported in the Company's Form 10-Q for the period ended March 31, 2012.
	(b) These measurement period adjustments were recorded to reflect an additional $1.0 million paid to the former HealthTran owners for the working capital reconciliation and changes in the estimated fair values of the associated assets acquired and liabilities assumed based on factors existing as of the acquisition date.
Schedule of estimated fair values and useful lives of intangible assets acquired	'
	The estimated fair values and useful lives of intangible assets acquired are as follows (dollars in thousands):
		Fair Value				Useful Life
	Trademarks/Trade names	$	1,750			6 months
	Customer relationships	69,800				4-9 years
	Non-compete agreements	2,600				5 years
	License	380				3 years
	Total	$	74,530

Goodwill_and_Other_Intangible_1

Goodwill and Other Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'
Changes in carrying amounts of goodwill by reportable segments	'
	The changes in the carrying amounts of goodwill by reportable segment for the nine months ended September 30, 2013 are as follows (in thousands):
		PBM		HCIT			Total
	Balance at December 31, 2012	4,458,373		19,665			4,478,038
	Measurement period adjustments (a)	16,472		—			16,472
	Acquisitions	3,111		—			3,111
	Balance at September 30, 2013	4,477,956		19,665			4,497,621
	a)	Adjustments to the fair value of assets acquired and liabilities assumed for recent acquisitions during the measurement period. The measurement period adjustments were not recast to the 2012 consolidated financial statements as they were not deemed material.
Components of intangible assets	'
	Definite-lived intangible assets are amortized over the useful lives of the related assets. The components of intangible assets were as follows (in thousands):
		September 30, 2013								December 31, 2012
		Gross Carrying Amount			Accumulated Amortization			Net		Gross Carrying Amount		Accumulated Amortization		Net
	Customer relationships	$	1,349,774		$	300,899		$	1,048,875	$	1,346,874	$	155,343	$	1,191,531
	Acquired software	—			—			—		3,765		3,765		—
	Trademarks/Tradenames	—			—			—		14,070		14,070		—
	Non-compete agreements	10,410			5,821			4,589		10,410		4,294		6,116
	Licenses	2,060			1,001			1,059		2,060		716		1,344
	Total	$	1,362,244		$	307,721		$	1,054,523	$	1,377,179	$	178,188	$	1,198,991

Debt_Tables

Debt (Tables)	9 Months Ended
	Sep. 30, 2013
Debt Disclosure [Abstract]	'
Components of long-term debt	'
	The following table sets forth the components of our long-term debt (in thousands) as of September 30, 2013 and December 31, 2012.
		30-Sep-13			31-Dec-12
	Senior secured term loan facility with an interest rate of 1.81% and 2.25% at September 30, 2013 and December 31, 2012, respectively	$	970,360		$	1,073,403
	Senior secured revolving credit facility due June 1, 2018 with an interest rate of 1.81% and 2.25% at September 30, 2013 and December 31, 2012, respectively	50,000			100,000
	Less current maturities	(43,750		)	(41,250		)
	Long-term debt	$	976,610		$	1,132,153
Schedule of maturities of principal amounts outstanding under Revolving Facility	'
	Principal repayments on the Term Loan Facility will be due as follows (in thousands):
	Year	Amount due
	2013	$	12,500
	2014	43,750
	2015	68,750
	2016	93,750
	2017	118,750
	2018	656,250
	Total	$	993,750

Common_Shares_and_StockBased_C1

Common Shares and Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Schedule of fair value assumptions	'
	The Black-Scholes option-pricing model was used to estimate the fair value of the stock options issued in each period at the grant date. Below is a summary of options granted and the assumptions utilized to derive fair value of the stock options under the Black-Scholes option-pricing model:
		Nine Months Ended September 30,
		2013			2012
	Total stock options granted	367,195			404,652
	Volatility	41.8% - 45.4%			47.2% - 49.2%
	Risk-free interest rate	0.81% - 1.74%			0.65% - 0.83%
	Expected life (in years)	4.5			4.5
	Dividend yield	—			—
	Weighted-average grant date fair value	$	21.44		$	29.4
Schedule of stock option activity	'
	The table below summarizes the stock options outstanding as of September 30, 2013 under both plans.
			Options Outstanding		Weighted Average Exercise Price				Unrecognized compensation cost			Weighted Average Period
									(in thousands)
	LTIP Plan
	Canadian Options		3,064		$	3.35
	U.S.Options		1,373,474		$	30.84			$	10,140		2.72
	Assumed Plans
	U.S.Options		49,665		$	56.21			$	876		$	3.45
Schedule of restricted stock units activity	'
	The table below summarizes the number of time-based and performance-based RSUs that were granted and outstanding under both plans for the nine months ended September 30, 2013:
		LTIP Plan									Assumed Plans
		Number of Restricted Stock Units									Number of Restricted Stock Units
		Time-Based		Performance - Based			Weighted Average Grant Date Fair Value Per Unit				Time-Based		Performance - Based	Weighted Average Grant Date Fair Value Per Unit
	Granted	251,970		253,980			$	56.25			130,320		25,570	$	55.78
	Outstanding	702,978		674,496							205,830		17,510
Schedule of unrecognized compensation expenses	'
	The table below summarizes the unrecognized compensation cost related to the outstanding RSUs at September 30, 2013.
		Unrecognized Compensation Cost			Weighted Average Period
		(in thousands)
	LTIP	$	35,200		2.37
	Assumed Plans	$	9,832		3.16

Segment_Information_Tables

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2013
Segment Reporting [Abstract]	'
Schedule of financial information by segment	'
	The Company reports in two operating segments: PBM and HCIT. The Company evaluates segment performance based upon revenue and gross profit. Financial information by segment is presented below (in thousands):
		Three Months Ended September 30,				Nine Months Ended September 30,
		2013		2012		2013		2012
	PBM:
	Revenue	$	3,578,767	$	3,150,755	$	10,142,515	$	6,493,029
	Cost of revenue	3,310,636		2,940,060		9,399,949		6,094,664
	Gross profit	$	268,131	$	210,695	$	742,566	$	398,365
	Total assets at September 30	$	7,115,563	$	7,146,899	$	7,115,563	$	7,146,899
	HCIT:
	Revenue	$	35,381	$	40,025	$	108,780	$	117,551
	Cost of revenue	15,724		15,829		50,597		48,132
	Gross profit	$	19,657	$	24,196	$	58,183	$	69,419
	Total assets at September 30	$	377,323	$	226,309	$	377,323	$	226,309
	Consolidated:
	Revenue	$	3,614,148	$	3,190,780	$	10,251,295	$	6,610,580
	Cost of revenue	3,326,360		2,955,889		9,450,546		6,142,796
	Gross profit	$	287,788	$	234,891	$	800,749	$	467,784
	Total assets at September 30	$	7,492,886	$	7,373,208	$	7,492,886	$	7,373,208

Fair_Value_Tables

Fair Value (Tables)	9 Months Ended
	Sep. 30, 2013
Fair Value Disclosures [Abstract]	'
Fair Value, Measurement Inputs, Disclosure [Table Text Block]	'
	For assets and liabilities measured at fair value on a recurring basis in the consolidated balance sheets, the table below categorizes fair value measurements across the three levels as of September 30, 2013 and December 31, 2012 (in thousands):
		September 30, 2013
		Quoted Prices in Active Markets (Level 1)		Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
	Liabilities:
	Contingent purchase price consideration	$	—	$	—	$	19,840	$	19,840
	Derivative	$	—	$	1,751	$	—	$	1,751
		December 31, 2012
		Quoted Prices in Active Markets (Level 1)		Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
	Liabilities:
	Contingent purchase price consideration	$	—	$	—	$	49,183	$	49,183
	Derivative	$	—	$	2,639	$	—	$	2,639

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]	'
Schedule of weighted average number of shares	'
	The following is the reconciliation between the number of weighted average shares used in the basic and diluted EPS calculations for the three and nine month periods ended September 30, 2013 and 2012:
		Three Months Ended September 30,		Nine Months Ended September 30,
		2013	2012	2013	2012
	Weighted average number of shares used in computing basic EPS	206,203,263	203,505,355	205,920,803	153,850,043
	Add dilutive common stock equivalents:
	Outstanding stock options and restricted stock units (a)	621,355	933,693	716,120	1,127,139
	Weighted average number of shares used in computing diluted EPS	206,824,618	204,439,048	206,636,923	154,977,182
	(a) Excludes 746,691 and 1,212,910 common stock equivalents for the three-month periods ended September 30, 2013 and 2012 because their effect was anti-dilutive. Excludes 633,407 and 1,021,501 common stock equivalents for the nine-month periods ended September 30, 2013 and 2012 because their effect was anti-dilutive.

Stock_Split_Details

Stock Split (Details)	0 Months Ended	1 Months Ended
	Sep. 06, 2012	Oct. 31, 2012
Equity [Abstract]	'	'
Number of common shares received after stock split	2	2

Business_Combinations_Catalyst

Business Combinations Catalyst (Details) (USD $)

0 Months Ended

1 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

9 Months Ended

0 Months Ended

Sep. 06, 2012

Oct. 31, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Jul. 02, 2012

Sep. 30, 2012

Jul. 02, 2012

Jul. 02, 2012

Jul. 02, 2012

Jul. 02, 2012

Catalyst

Catalyst

Catalyst

Catalyst

Catalyst

Common Stock

Common Stock

Initial Amounts Recognized at Acquisition Date

Prior Measurement Period Adjustments

Current Measurement Period Adjustments

Catalyst

Catalyst

Catalyst

Catalyst

Merger Agreement [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stock conversion, share received per share converted

'

'

'

'

'

'

'

'

'

'

'

'

1.3212

'

'

'

Stock conversion, cash received per share converted, prior to stock split

'

'

'

'

'

'

'

'

'

'

'

'

0.6606

'

'

'

Number of common shares received after stock split

2

2

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stock conversion, cash received per share converted

'

'

'

'

'

'

'

'

'

'

$28

'

'

'

'

'

Shares issued

'

'

'

'

'

'

'

'

'

'

'

11,960,000

66,800,000

'

'

'

Warrants issued

'

'

'

'

'

'

'

'

'

'

'

'

500,000

'

'

'

Revenue from acquired company included in consolidated statement of operations

'

'

'

'

'

'

$1,900,000,000

$1,500,000,000

$5,300,000,000

$1,500,000,000

'

'

'

'

'

'

Goodwill expected to be tax deductible

'

'

'

'

'

'

'

'

'

'

525,000,000

'

'

'

'

'

Amortization of intangible assets

'

'

47,220,000

51,380,000

147,368,000

70,710,000

40,000,000

'

126,000,000

'

'

'

'

'

'

'

Future amortization expense, remainder of 2013

'

'

47,100,000

'

47,100,000

'

40,000,000

'

40,000,000

'

'

'

'

'

'

'

Fair value of intangible assets

'

'

'

'

'

'

1,200,000,000

'

1,200,000,000

'

'

'

'

'

'

'

Customer relationships, weighted average useful life

'

'

'

'

'

'

'

'

'9 years

'

'

'

'

'

'

'

Business Acquisition, Cost of Acquired Entity, Purchase Price [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cash paid to shareholders

'

'

'

'

'

'

'

'

'

'

1,415,276,000

'

'

'

'

'

Fair value of common shares issued

'

'

'

'

'

'

'

'

'

'

3,238,141,000

[1]

'

'

'

'

'

Fair value of warrants and stock options issued

'

'

'

'

'

'

'

'

'

'

19,824,000

[2]

'

'

'

'

'

Total purchase price

'

'

'

'

'

'

'

'

'

'

4,673,241,000

'

'

'

'

'

Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cash and cash equivalents

'

'

'

'

'

'

'

'

'

'

93,460,000

'

'

93,775,000

[3]

-315,000

[4]

0

[5]

Other current assets

'

'

'

'

'

'

'

'

'

'

703,501,000

'

'

695,888,000

[3]

5,202,000

[4]

2,411,000

[5]

Total current assets

'

'

'

'

'

'

'

'

'

'

796,961,000

'

'

789,663,000

[3]

4,887,000

[4]

2,411,000

[5]

Goodwill

'

'

'

'

'

'

'

'

'

'

4,034,868,000

'

'

4,010,235,000

[3]

8,492,000

[4]

16,141,000

[5]

Customer relationships intangible

'

'

'

'

'

'

'

'

'

'

1,184,800,000

'

'

1,184,800,000

[3]

0

[4]

0

[5]

Other long-term assets

'

'

'

'

'

'

'

'

'

'

88,729,000

'

'

87,174,000

[3]

1,547,000

[4]

8,000

[5]

Total assets acquired

'

'

'

'

'

'

'

'

'

'

6,105,358,000

'

'

6,071,872,000

[3]

14,926,000

[4]

18,560,000

[5]

Accounts Payable

'

'

'

'

'

'

'

'

'

'

338,824,000

'

'

338,819,000

[3]

0

[4]

5,000

[5]

Pharmacy benefit management rebates payable

'

'

'

'

'

'

'

'

'

'

177,615,000

'

'

176,202,000

[3]

2,935,000

[4]

-1,522,000

[5]

Accrued expenses and other current liabilities

'

'

'

'

'

'

'

'

'

'

194,672,000

'

'

187,851,000

[3]

1,348,000

[4]

5,473,000

[5]

Long-term debt

'

'

'

'

'

'

'

'

'

'

311,994,000

'

'

311,994,000

[3]

0

[4]

0

[5]

Other long-term liabilities

'

'

'

'

'

'

'

'

'

'

410,622,000

'

'

385,375,000

[3]

10,643,000

[4]

14,604,000

[5]

Total liabilities assumed

'

'

'

'

'

'

'

'

'

'

1,433,727,000

'

'

1,400,241,000

[3]

14,926,000

[4]

18,560,000

[5]

Non-controlling interest

'

'

'

'

'

'

'

'

'

'

-1,610,000

'

'

-1,610,000

[3]

0

[4]

0

[5]

Net assets acquired

'

'

'

'

'

'

'

'

'

'

$4,673,241,000

'

'

$4,673,241,000

[3]

$0

[4]

$0

[5]

[1]

Valued based on the number of outstanding shares immediately prior to the Merger multiplied by the exchange ratio of 1.3212 (0.6606 prior to the October 2012 two-for-one stock split), multiplied by the closing market price of Catamaran shares on July 2, 2012.

[2]

The Black-Scholes pricing model was used to calculate the fair value of the replacement warrants and stock options issued.

[3]

As previously reported in the Company's Form 10-Q for the period ended September 30, 2012.

[4]

These measurement period adjustments were recorded to reflect an additional $1.0 million paid to the former HealthTran owners for the working capital reconciliation and changes in the estimated fair values of the associated assets acquired and liabilities assumed based on factors existing as of the acquisition date.

[5]

These represent measurement period adjustments during 2013 through the end of the measurement period and were recorded to reflect changes in the estimated fair values of the associated assets acquired and liabilities assumed based on factors existing as of the acquisition date.

Business_Combinations_HealthTr

Business Combinations HealthTran (Details) (USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013	Jan. 31, 2012
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net [Abstract]	'	'	'
Future amortization expense, remainder of 2013	$47,100,000	$47,100,000	'
HealthTran	'	'	'
Business Acquisition [Line Items]	'	'	'
Cash paid to shareholders	'	'	250,000,000
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net [Abstract]	'	'	'
Customer relationships intangible	74,530,000	74,530,000	'
Amortization of Acquired Intangible Assets	3,600,000	10,900,000	'
Future amortization expense, remainder of 2013	3,600,000	3,600,000	'
Initial Amounts Recognized at Acquisition Date | HealthTran	'	'	'
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net [Abstract]	'	'	'
Total current assets	'	'	30,654,000	[1]
Property and equipment	'	'	2,787,000	[1]
Goodwill	'	'	173,642,000	[1]
Customer relationships intangible	'	'	77,130,000	[1]
Total assets acquired	'	'	284,213,000	[1]
Current liabilities	'	'	36,784,000	[1]
Total liabilities assumed	'	'	36,784,000	[1]
Net assets acquired	'	'	247,429,000	[1]
Measurement Period Adjustments | HealthTran	'	'	'
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net [Abstract]	'	'	'
Total current assets	'	'	245,000	[2]
Goodwill	'	'	833,000	[2]
Customer relationships intangible	'	'	-2,600,000	[2]
Total assets acquired	'	'	-1,522,000	[2]
Current liabilities	'	'	-496,000	[2]
Total liabilities assumed	'	'	-496,000	[2]
Net assets acquired	'	'	-1,026,000	[2]
Payments due to previous owners	'	1,000,000	'
Current Amounts Recognized at Acquisition Date | HealthTran	'	'	'
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net [Abstract]	'	'	'
Total current assets	'	'	30,899,000
Property and equipment	'	'	2,787,000
Goodwill	'	'	174,475,000
Customer relationships intangible	'	'	74,530,000
Total assets acquired	'	'	282,691,000
Current liabilities	'	'	36,288,000
Total liabilities assumed	'	'	36,288,000
Net assets acquired	'	'	246,403,000
Trademarks/Trade names | HealthTran	'	'	'
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net [Abstract]	'	'	'
Customer relationships intangible	1,750,000	1,750,000	'
Customer relationships, weighted average useful life	'	'6 months	'
Customer relationships | HealthTran	'	'	'
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net [Abstract]	'	'	'
Customer relationships intangible	69,800,000	69,800,000	'
Non-compete agreements | HealthTran	'	'	'
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net [Abstract]	'	'	'
Customer relationships intangible	2,600,000	2,600,000	'
Customer relationships, weighted average useful life	'	'5 years	'
License | HealthTran	'	'	'
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net [Abstract]	'	'	'
Customer relationships intangible	$380,000	$380,000	'
Customer relationships, weighted average useful life	'	'3 years	'
Minimum | Customer relationships | HealthTran	'	'	'
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net [Abstract]	'	'	'
Customer relationships, weighted average useful life	'	'4 years	'
Maximum | Customer relationships | HealthTran	'	'	'
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net [Abstract]	'	'	'
Customer relationships, weighted average useful life	'	'9 years	'
[1]	As previously reported in the Company's Form 10-Q for the period ended March 31, 2012.
[2]	These represent measurement period adjustments from the acquisition date through December 31, 2012 and were recorded to reflect changes in the estimated fair values of the associated assets acquired and liabilities assumed based on factors existing as of the acquisition date.

Business_Combinations_Pro_Form

Business Combinations Pro Forma Information (Details) (USD $)	9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2012
Business Acquisition, Pro Forma Information [Abstract]	'
Revenue	$9,609,135
Gross profit	654,852
Net income	$79,424
Earnings per share attributable to the Company:	'
Basic (in dollars per share)	$0.39
Diluted (in dollars per share)	$0.39
Weighted average number of shares used in computing earnings per share:	'
Basic (in shares)	204,350,003
Diluted (in shares)	205,477,142

Business_Combinations_Restat_D

Business Combinations Restat (Details) (Subsequent Event [Member], Restat, LLC [Member], USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013
		Revolving Credit Facility [Member]
Business Acquisition [Line Items]	'	'
Purchase price	$409,500,000	'
Line of credit, outstanding balance	'	$350,000,000

Goodwill_and_Other_Intangible_2

Goodwill and Other Intangible Assets (Details) 1 (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013		Sep. 30, 2013		Sep. 30, 2013	Dec. 31, 2012
			P B M		H C I T	H C I T
Goodwill [Roll Forward]	'		'		'	'
Goodwill, Beginning Balance	$4,478,038		$4,458,373		$19,665	$19,665
Goodwill, Measurement period adjustment	16,472	[1]	16,472	[1]	'	'
Goodwill, Acquisitions	3,111		3,111		'	'
Goodwill, Ending Balance	$4,497,621		$4,477,956		$19,665	$19,665
[1]	Adjustments to the fair value of assets acquired and liabilities assumed for recent acquisitions during the measurement period. The measurement period adjustments were not recast to the 2012 consolidated financial statements as they were not deemed material.

Goodwill_and_Other_Intangible_3

Goodwill and Other Intangible Assets (Details) 2 (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	$1,362,244	$1,377,179
Accumulated Amortization	307,721	178,188
Net	1,054,523	1,198,991
Customer relationships	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	1,349,774	1,346,874
Accumulated Amortization	300,899	155,343
Net	1,048,875	1,191,531
Acquired software	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	0	3,765
Accumulated Amortization	0	3,765
Net	0	0
Trademarks/Trade names	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	0	14,070
Accumulated Amortization	0	14,070
Net	0	0
Non-compete agreements	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	10,410	10,410
Accumulated Amortization	5,821	4,294
Net	4,589	6,116
License	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	2,060	2,060
Accumulated Amortization	1,001	716
Net	$1,059	$1,344

Goodwill_and_Other_Intangible_4

Goodwill and Other Intangible Assets (Details) 3 (USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013
Finite-Lived Intangible Assets, Future Amortization Expense [Abstract]	'	'
Future amortization expense, remainder of 2013	$47,100,000	$47,100,000
Future amortization expense, 2014	179,500,000	179,500,000
Future amortization expense, 2015	164,400,000	164,400,000
Future amortization expense, 2016	142,900,000	142,900,000
Future amortization expense, 2017	131,500,000	131,500,000
Future amortization expense, 2018	122,400,000	122,400,000
Total future amortization expense	266,700,000	266,700,000
Impairment of goodwill	$0	$0

Debt_Details

Debt (Details) (USD $)

3 Months Ended

9 Months Ended

9 Months Ended

9 Months Ended

0 Months Ended

0 Months Ended

1 Months Ended

9 Months Ended

0 Months Ended

3 Months Ended

9 Months Ended

Sep. 30, 2013

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2013

Jun. 03, 2013

Jun. 03, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Dec. 31, 2012

Jul. 02, 2012

Sep. 30, 2013

Jul. 02, 2012

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2012

Jul. 02, 2012

Jun. 03, 2013

Jul. 31, 2013

Sep. 30, 2013

Jul. 02, 2012

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2012

Jul. 02, 2012

Sep. 30, 2013

Jun. 03, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Credit Agreement

Amended Credit Agreement [Member]

Amended Credit Agreement [Member]

Amended Credit Agreement [Member]

Revolving Facility [Member]

Revolving Facility [Member]

Revolving Facility [Member]

Revolving Facility [Member]

Revolving Facility [Member]

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Secured Debt

Restat, LLC [Member]

Minimum

Maximum

Base Rate Borrowings

LIBOR Borrowings

Credit Agreement

Credit Agreement

Credit Agreement

Credit Agreement

Amended Credit Agreement [Member]

Amended Credit Agreement [Member]

Term-A Facility

Term-A Facility

Term-A Facility

Term-A Facility

Term-A Facility

Term-A Facility

Term-A Facility

Term-A Facility

Term-A Facility

Revolving Facility [Member]

Revolving Facility [Member]

Revolving Facility [Member]

Revolving Facility [Member]

Revolving Facility [Member]

Revolving Facility [Member]

Revolving Facility [Member]

Revolving Facility [Member]

Subsequent Event [Member]

Amended Credit Agreement [Member]

Amended Credit Agreement [Member]

Beginning With The Fiscal Quarter Ending December 31, 2012

Beginning With The Fiscal Quarter Ending December 31, 2013

Beginning With The Fiscal Quarter Ending December 31, 2014

Credit Agreement

Credit Agreement

Credit Agreement

Amended Credit Agreement [Member]

Amended Credit Agreement [Member]

Amended Credit Agreement [Member]

Credit Agreement

Credit Agreement

Credit Agreement

Amended Credit Agreement [Member]

Amended Credit Agreement [Member]

Revolving Credit Facility [Member]

LIBOR Borrowings

LIBOR Borrowings

Long-term Debt, by Category, Current and Noncurrent [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Long-term Debt

'

'

'

'

'

'

'

'

'

'

'

$993,750,000

'

'

'

'

'

$970,360,000

$1,073,403,000

'

'

'

'

'

$993,800,000

'

$50,000,000

$100,000,000

'

'

'

'

'

'

'

'

Less current maturities

-43,750,000

-43,750,000

-41,250,000

'

'

'

'

'

'

'

'

'

-43,750,000

-41,250,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Long-term debt

976,610,000

976,610,000

1,132,153,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stated percentage

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1.81%

2.25%

'

'

'

'

'

'

'

1.81%

2.25%

'

'

'

'

'

'

Debt amount

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,800,000,000

'

'

'

'

'

'

1,100,000,000

1,000,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Line of credit, remaining borrowing capacity

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

750,000,000

700,000,000

'

'

'

Proceeds from Lines of Credit

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

350,000,000

'

'

Repayments of long-term debt

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

6,300,000

'

'

'

'

'

'

'

'

'

'

'

'

Payment of direct lender fees

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2,300,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Payment of debt discount incurred

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,300,000

'

'

'

'

'

'

'

'

'

'

'

Debt issuance cost paid

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,000,000

'

'

'

'

Repayment of credit facility

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

50,000,000

'

'

'

'

Term of long-term debt

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'5 years

'

'

'

'

'

'

'

'

'5 years

'

'

'

'

'

'

'

'

'

'

Line of credit borrowing capacity

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

700,000,000

'

'

'

'

'

'

800,000,000

'

'

'

Debt discount

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

24,100,000

'

'

'

'

'

'

'

'

16,600,000

'

'

'

'

'

Amortization related to financing costs and debt discounts

2,100,000

7,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Initial applicable margin for borrowings

'

'

'

'

'

0.63%

1.63%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Interest rate on amounts drawn

'

'

'

2.25%

1.81%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt prepayment made

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

100,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Leverage ratio

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1.5

2.5

Maximum leverage ratio

'

'

'

'

'

'

'

3.75

3.5

3.25

3

4

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Maximum consolidated senior secured leverage ratio

'

'

'

'

'

'

'

'

'

'

'

3.25

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Maximum ratio of EBIT to interest expense

'

'

'

'

'

'

'

'

'

'

'

4

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Interest expense from unamortized debt discount and debt issuance costs

'

$400,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt_Debt_Maturities_Details

Debt Debt Maturities (Details) (Amended Credit Agreement [Member], Revolving Facility [Member], USD $)	Sep. 30, 2013
In Thousands, unless otherwise specified
Amended Credit Agreement [Member] | Revolving Facility [Member]	'
Long-term Debt, Fiscal Year Maturity [Abstract]	'
2013	$12,500
2014	43,750
2015	68,750
2016	93,750
2017	118,750
2018	656,250
Long-term Debt	$993,750

Common_Shares_and_StockBased_C2

Common Shares and Stock-Based Compensation (Details) 1 (USD $)	3 Months Ended		9 Months Ended			0 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2012	16-May-12	16-May-12	Jul. 02, 2012	Sep. 30, 2013	Sep. 30, 2013
					Common Stock	Public Offering	Public Offering	Catalyst	LTIP [Member]	Assumed Plans
							Common Stock	Common Stock
Stockholders' Equity [Line Items]	'	'	'	'	'	'	'	'	'	'
Shares from public offering	'	'	'	'	11,960,000	'	11,960,000	66,800,000	'	'
Share price to public	'	'	'	'	'	'	$45.30	'	'	'
Proceeds from public offering, net of issuance costs	'	'	$0	$518,813	'	$519,100	'	'	'	'
Warrants issued	'	'	'	'	'	'	'	500,000	'	'
Stock-based compensation	$6,600	$6,300	$19,724	$13,161	'	'	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	'	'	'	'	'	'	'	'	6,867,399	1,053,891

Common_Shares_and_StockBased_C3

Common Shares and Stock-Based Compensation (Details) 2 (USD $)

9 Months Ended

1 Months Ended

9 Months Ended

Sep. 30, 2013

Sep. 30, 2012

Jul. 31, 2012

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Stock Options

Stock Options

LTIP Plan

Assumed Plans

Minimum

Minimum

Minimum

Minimum

Maximum

Maximum

Maximum

Maximum

Stock Options

Stock Options

Stock Options

Stock Options

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

Incremental number of shares authorized

'

'

5,000,000

'

'

'

'

'

'

'

'

'

Maximum common shares issued under plan

'

'

'

1,480,936

'

'

'

'

'

'

'

'

Stock-based awards available for grant

'

'

'

1,053,891

'

'

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

Total stock options granted

367,195

404,652

'

'

'

'

'

'

'

'

'

'

Volatility

'

'

'

'

41.80%

47.20%

'

'

45.40%

49.23%

'

'

Risk-free interest rate

'

'

'

'

'

'

0.81%

0.65%

'

'

1.74%

0.83%

Expected life (in years)

'4 years 6 months

'4 years 6 months

'

'

'

'

'

'

'

'

'

'

Dividend yield

0.00%

0.00%

'

'

'

'

'

'

'

'

'

'

Weighted-average grant date fair value (in dollars per share)

$21.44

$29.40

'

'

'

'

'

'

'

'

'

'

Common_Shares_and_StockBased_C4

Common Shares and Stock-Based Compensation (Details) 3 (Stock Options, USD $)	9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013
CANADA | LTIP Plan	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Options Outstanding (in shares)	3,064
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$3.35
UNITED STATES | LTIP Plan	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Unrecognized compensation costs on nonvested awards, weighted average period of recognition (in years)	'2 years 8 months 19 days
Options Outstanding (in shares)	1,373,474
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$30.84
Unrecognized compensation cost	$10,140
UNITED STATES | Assumed Plans	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Unrecognized compensation costs on nonvested awards, weighted average period of recognition (in years)	'3 years 5 months 12 days
Options Outstanding (in shares)	49,665
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$56.21
Unrecognized compensation cost	$876

Common_Shares_and_StockBased_C5

Common Shares and Stock-Based Compensation (Details) 4 (USD $)	9 Months Ended
	Sep. 30, 2013
Restricted Stock Units Performance Based	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Vesting period	'3 years
LTIP Plan | Restricted Stock Units Time Based	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Number of restricted units granted	251,970
Number of restricted units outstanding	702,978
LTIP Plan | Restricted Stock Units Performance Based	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Number of restricted units granted	253,980
Number of restricted units outstanding	674,496
LTIP Plan | Restricted Stock Units (RSUs)	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Weighted average grant date value of restricted units granted (per unit)	56.25
Catalyst | Restricted Stock Units Time Based	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Number of restricted units granted	130,320
Number of restricted units outstanding	205,830
Catalyst | Restricted Stock Units Performance Based	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Number of restricted units granted	25,570
Number of restricted units outstanding	17,510
Catalyst | Restricted Stock Units (RSUs)	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Weighted average grant date value of restricted units granted (per unit)	55.78
Straight Line Vesting Basis | Restricted Stock Units Time Based | Minimum	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Vesting period	'2 years
Straight Line Vesting Basis | Restricted Stock Units Time Based | Maximum	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Vesting period	'4 years
Cliff Vesting | Restricted Stock Units Time Based | Minimum	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Vesting period	'3 years
Cliff Vesting | Restricted Stock Units Time Based | Maximum	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Vesting period	'4 years

Common_Shares_and_StockBased_C6

Common Shares and Stock-Based Compensation (Details) 5 (Restricted Stock Units (RSUs), USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013
LTIP Plan	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Unrecognized compensation costs on nonvested awards	$35,200
Unrecognized compensation costs on nonvested awards, weighted average period of recognition (in years)	'2 years 4 months 13 days
Assumed Plans	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Unrecognized compensation costs on nonvested awards	$9,832
Unrecognized compensation costs on nonvested awards, weighted average period of recognition (in years)	'3 years 1 month 28 days

Segment_Information_Details

Segment Information (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
			segment
Segment Reporting Information [Line Items]	'	'	'	'	'
Number of operating segments	'	'	2	'	'
Revenues	$3,614,148	$3,190,780	$10,251,295	$6,610,580	'
Cost of revenue	3,326,360	2,955,889	9,450,546	6,142,796	'
Gross profit	287,788	234,891	800,749	467,784	'
Total assets	7,492,886	7,373,208	7,492,886	7,373,208	7,385,127
P B M	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	3,578,767	3,150,755	10,142,515	6,493,029	'
Cost of revenue	3,310,636	2,940,060	9,399,949	6,094,664	'
Gross profit	268,131	210,695	742,566	398,365	'
Total assets	7,115,563	7,146,899	7,115,563	7,146,899	'
H C I T	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenues	35,381	40,025	108,780	117,551	'
Cost of revenue	15,724	15,829	50,597	48,132	'
Gross profit	19,657	24,196	58,183	69,419	'
Total assets	$377,323	$226,309	$377,323	$226,309	'

Income_Taxes_Details

Income Taxes (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Income Tax Disclosure [Abstract]	'	'	'	'
Effective income tax rate	25.20%	39.80%	26.40%	37.20%

Financial_Instruments_Details

Financial Instruments (Details) (USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013
Derivative [Line Items]	'	'
Length of interest rate swap	'	'3 years
Notional amount of interest rate cash flow hedge derivatives	$500,000,000	$500,000,000
Deferred expenses related to derivative instruments	1,700,000	1,700,000
Fair Value, Measurements, Recurring	'	'
Derivative [Line Items]	'	'
Cash flow hedge loss reclassified to interest expense	400,000	1,100,000
Cash Flow Hedging | Interest Rate Contract	'	'
Derivative [Line Items]	'	'
Libor rate	0.52%	0.52%
Effective interest rate	2.14%	2.14%
Basis spread on variable rate	1.63%	1.63%
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring	'	'
Derivative [Line Items]	'	'
Fair value of interest rate swap	$1,751,000	$1,751,000

Fair_Value_Details

Fair Value (Details) (USD $)	3 Months Ended	9 Months Ended			9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2012
			Fair Value, Measurements, Recurring	Fair Value, Measurements, Recurring	Fair Value, Measurements, Recurring	Fair Value, Measurements, Recurring	Fair Value, Measurements, Recurring	Fair Value, Measurements, Recurring
			Fair Value, Inputs, Level 2	Fair Value, Inputs, Level 2	Fair Value, Inputs, Level 3	Fair Value, Inputs, Level 3	Estimate of Fair Value, Fair Value Disclosure	Estimate of Fair Value, Fair Value Disclosure
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'	'	'	'	'	'	'
Contingent purchase price consideration	'	'	'	'	$19,840,000	$49,183,000	$19,840,000	$49,183,000
Derivative	'	'	'	2,639,000	'	'	1,751,000	2,639,000
Payments made to reduce the fair value or contingent purchase price considerations	'	'	'	'	25,500,000	'	'	'
Adjustments made to reduce the fair value of contingent purchase price considerations	'	'	'	'	4,500,000	'	'	'
Contingent consideration, change in value of contingent purchase price	-100,000	-500,000	'	'	'	'	'	'
Fair value of interest rate swap	'	'	$1,751,000	'	'	'	'	'

Lease_Exit_Costs_Details

Lease Exit Costs (Details) (USD $)	3 Months Ended	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2013
Operating Leased Assets [Line Items]	'	'
Leases payments, net of sub-lease receipts	'	$7.20
Selling, General and Administrative Expenses	'	'
Operating Leased Assets [Line Items]	'	'
Lease loss expense	5.6	6
Accrued Expenses and Other Current Liabilities	'	'
Operating Leased Assets [Line Items]	'	'
Lease loss accrual	$5.60	$5.60

Earnings_Per_Share_Details_1

Earnings Per Share (Details) 1	3 Months Ended				9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Earnings Per Share [Abstract]	'		'		'		'
Weighted average number of shares used in computing basic EPS	206,203,263		203,505,355		205,920,803		153,850,043
Add dilutive common stock equivalents:	'		'		'		'
Outstanding stock options and restricted stock units	621,355	[1]	933,693	[1]	716,120	[1]	1,127,139	[1]
Weighted average number of shares used in computing diluted EPS	206,824,618		204,439,048		206,636,923		154,977,182
[1]	Excludes 746,691 and 1,212,910 common stock equivalents for the three-month periods ended September 30, 2013 and 2012 because their effect was anti-dilutive. Excludes 633,407 and 1,021,501 common stock equivalents for the nine-month periods ended September 30, 2013 and 2012 because their effect was anti-dilutive.

Earnings_Per_Share_Details_2

Earnings Per Share (Details) 2 (Anti-dilutive Stock Options and RSU)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Anti-dilutive Stock Options and RSU	'	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'	'
Antidilutive securities excluded from computation of earnings per share, amount	746,691	1,212,910	633,407	1,021,501

Concentration_Risk_Details

Concentration Risk (Details) (Customer Concentration Risk)	3 Months Ended		9 Months Ended			12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Dec. 31, 2012	Dec. 31, 2012
	Sales	Sales	Sales	Sales	Accounts Receivable	Accounts Receivable	Accounts Receivable
					Customer One	Customer One	Customer Two
Concentration Risk [Line Items]	'	'	'	'	'	'	'
Concentration risk, percentage, period	19.00%	24.00%	19.00%	35.00%	'	'	'
Concentration risk, percentage	'	'	'	'	10.00%	13.00%	12.00%