Note 3 - Acquisitions (Detail) (USD $)	12 Months Ended					60 Months Ended			54 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended		3 Months Ended	12 Months Ended					12 Months Ended		12 Months Ended			12 Months Ended			12 Months Ended							12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008	Dec. 31, 2012	Dec. 31, 2011 Accrued [Member] MES Group [Member]	Dec. 31, 2011 Accrued [Member] Other 2011 Acquisitions [Member]	Dec. 31, 2012 Southwest Medical Acquisition [Member]	Dec. 31, 2010 Metro Medical [Member]	Sep. 30, 2011 Direct IME [Member]	Dec. 31, 2010 Direct IME [Member]	Dec. 31, 2010 Verity [Member]	Dec. 31, 2010 UKIM [Member]	Dec. 31, 2011 UKIM [Member]	Dec. 31, 2011 Other 2010 Acquisitions [Member]	Dec. 31, 2010 Other 2010 Acquisitions [Member]	Dec. 31, 2010 Network Medical Review Co Ltd [Member]	Dec. 31, 2010 Exigere Corporation [Member]	Dec. 31, 2010 SOMA [Member]	Dec. 31, 2011 SOMA [Member]	Dec. 31, 2011 MES Group [Member]	Feb. 28, 2011 MES Group [Member]	Dec. 31, 2010 MES Group [Member]	Dec. 31, 2012 Other 2011 Acquisitions [Member]	Dec. 31, 2011 Other 2011 Acquisitions [Member]	Dec. 31, 2010 Other 2011 Acquisitions [Member]	Dec. 31, 2011 Premex Group [Member]	May 10, 2011 Premex Group [Member]	Dec. 31, 2011 National IME Centres Inc. [Member]	Dec. 31, 2011 MLS Group of Companies Inc. [Member]	Dec. 31, 2012 MedHealth Holdings [Member]	Dec. 31, 2012 Parthenia Medical Group [Member]	Dec. 31, 2012 Other 2012 Acquisitions [Member]	Dec. 31, 2012 Pro Forma Additional Expenses [Member]	Dec. 31, 2011 Pro Forma Additional Expenses [Member]
Number of Businesses Acquired	3	9	14	11	3	40			40
Business Acquisition, Cost of Acquired Entity, Purchase Price	$ 109,200,000					$ 109,200,000				$ 13,500,000		$ 13,600,000	$ 14,000,000	$ 16,000,000			$ 70,200,000					$ 215,000,000				$ 43,200,000		$ 108,400,000
Business Acquisition, Cost of Acquired Entity, Cash Paid	112,000,000					112,000,000				13,000,000		11,900,000		14,500,000			62,800,000					175,000,000				44,600,000		66,500,000
Business Acquisition, Purchase Price Allocation, Current Assets, Cash and Cash Equivalents	2,900,000					2,900,000				722,000							1,000,000									564,000
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in Shares)	6,190		507,606							589,930				253,003			1,685,312					1,424,501				214,926		661,610
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned	85,000					85,000				1,300,000		1,400,000		1,500,000			5,900,000					30,000,000				2,000,000		15,100,000
Business Acquisition, Cost of Acquired Entity, Transaction Costs	1,300,000					1,300,000	2,000,000	659,000		101,000		194,000	138,000	447,000			1,200,000					535,000		1,500,000		562,000	55,000	646,000
Cash Acquired from Acquisition			50,000
Business Acquisition, Contingent Consideration, Potential Cash Payment												351,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Consideration Transferred												210,000			373,000	88,000				714,000
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability	775,000										600,000
Business Combination, Step Acquisition, Equity Interest in Acquiree, Percentage														100.00%				100.00%
Business Acquisition, Cost of Acquired Entity, Liabilities Incurred			6,900,000														1,700,000
Business Acquisition, Contingent Consideration, at Fair Value																	786,000
Business Acquisition, Contingent Consideration, Shares Issuable (in Shares)																	135,282
Business Acquisition, Percentage of Voting Interests Acquired																			100.00%			100.00%						100.00%		100.00%	100.00%	100.00%	100.00%
Business Acquisition, Purchase Price Allocation, Goodwill, Expected Tax Deductible Amount	18,300,000					18,300,000															24,000,000					54,600,000								53,500,000
Business Acquisition, Purchase Price Allocation, Amortizable Intangible Assets																					21,700,000
Closing Price Per Share (in Dollars per share)																							$ 21.07						$ 22.85
Business Acquisition, Purchase Price Allocation, Liabilities Assumed																							10,000,000					26,800,000
Reduction Of Total Consideration Paid	1,500,000
Business Acquisition Purchase Price Allocation Intangible Assets Expected Tax Deductible Amount	20,800,000					20,800,000																												50,200,000
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual																									22,900,000
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual																									1,500,000
Interest Expense	2,200,000	1,900,000	872,000																																5,100,000	14,800,000
Depreciation, Depletion and Amortization	58,551,000	47,439,000	19,505,000																																9,300,000	22,900,000
Selling, General and Administrative Expense	$ 113,510,000	$ 84,133,000	$ 37,689,000																																$ 4,600,000	$ 16,300,000