Note 14 - Condensed Consolidating Financial Information of Guarantor Subsidiaries (Details) - Condensed Consolidating Statement of Cash Flows (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities	$ 45,199,000	$ 36,355,000	$ 24,777,000
Investing activities:
Cash paid for acquisitions, net	(187,402,000)	(3,318,000)	(108,970,000)
Purchases of equipment and leasehold improvements, net	(10,894,000)	(6,544,000)	(5,841,000)
Working capital and other settlements for acquisitions	(2,331,000)	(569,000)	427,000
Proceeds from foreign currency net investment hedge	4,006,000	1,421,000
Other	(1,542,000)	(1,144,000)
Net cash used in investing activities	(198,163,000)	(10,154,000)	(114,384,000)
Financing activities:
Borrowings under senior secured revolving credit facility	299,255,000	142,473,000	170,640,000
Proceeds from the exercise of options and warrants	42,437,000	24,261,000	2,258,000
Excess tax benefit related to share-based compensation	9,287,000	6,610,000	2,853,000
Net borrowings (repayments) under working capital facilities	4,939,000	2,772,000	(6,279,000)
Purchases of stock for treasury			(387,000)
Payment of deferred financing costs	(263,000)	(172,000)	(1,074,000)
Repayment of subordinated unsecured notes payable	(333,000)	(270,000)	(2,193,000)
Payment of contingent earnout obligation	(4,362,000)
Repayment under senior secured revolving credit facility	(200,429,000)	(196,746,000)	(76,000,000)
Intercompany notes and investments and other	(53,000)		(94,000)
Net cash provided by (used in) financing activities	150,478,000	(21,072,000)	89,724,000
Exchange rate impact on cash and cash equivalents	(592,000)	(927,000)	94,000
Net increase (decrease) in cash and cash equivalents	(3,078,000)	4,202,000	211,000
Cash and cash equivalents, beginning of year	12,829,000	8,627,000	8,416,000
Cash and cash equivalents, end of year	9,751,000	12,829,000	8,627,000
Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities	33,096,000	23,963,000	18,131,000
Investing activities:
Cash paid for acquisitions, net	(177,864,000)	(592,000)	(12,378,000)
Purchases of equipment and leasehold improvements, net	(7,687,000)	(3,197,000)	(5,071,000)
Working capital and other settlements for acquisitions	(477,000)	(444,000)	(857,000)
Proceeds from foreign currency net investment hedge	4,006,000	1,421,000
Other	(1,347,000)	(1,144,000)
Net cash used in investing activities	(183,369,000)	(3,956,000)	(18,306,000)
Financing activities:
Repayment of subordinated unsecured notes payable	(333,000)	(270,000)	(2,193,000)
Intercompany notes and investments and other	150,234,000	(23,102,000)	449,000
Net cash provided by (used in) financing activities	149,901,000	(23,372,000)	(1,744,000)
Net increase (decrease) in cash and cash equivalents	(372,000)	(3,365,000)	(1,919,000)
Cash and cash equivalents, beginning of year	760,000	4,125,000	6,044,000
Cash and cash equivalents, end of year	388,000	760,000	4,125,000
Non-Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities	12,103,000	12,392,000	6,646,000
Investing activities:
Cash paid for acquisitions, net	(9,538,000)	(2,726,000)	(96,592,000)
Purchases of equipment and leasehold improvements, net	(3,207,000)	(3,347,000)	(770,000)
Working capital and other settlements for acquisitions	(1,854,000)	(125,000)	1,284,000
Other	(195,000)
Net cash used in investing activities	(14,794,000)	(6,198,000)	(96,078,000)
Financing activities:
Net borrowings (repayments) under working capital facilities	4,939,000	2,772,000	(6,279,000)
Payment of deferred financing costs		(116,000)
Payment of contingent earnout obligation	(4,362,000)
Intercompany notes and investments and other		(356,000)	97,747,000
Net cash provided by (used in) financing activities	577,000	2,300,000	91,468,000
Exchange rate impact on cash and cash equivalents	(592,000)	(927,000)	94,000
Net increase (decrease) in cash and cash equivalents	(2,706,000)	7,567,000	2,130,000
Cash and cash equivalents, beginning of year	12,069,000	4,502,000	2,372,000
Cash and cash equivalents, end of year	9,363,000	12,069,000	4,502,000
Parent Company [Member]
Financing activities:
Borrowings under senior secured revolving credit facility	299,255,000	142,473,000	170,640,000
Proceeds from the exercise of options and warrants	42,437,000	24,261,000	2,258,000
Excess tax benefit related to share-based compensation	9,287,000	6,610,000	2,853,000
Purchases of stock for treasury			(387,000)
Payment of deferred financing costs	(263,000)	(56,000)	(1,074,000)
Repayment under senior secured revolving credit facility	(200,429,000)	(196,746,000)	(76,000,000)
Intercompany notes and investments and other	$ (150,287,000)	$ 23,458,000	$ (98,290,000)