Note 11 - Variable Interest Entities (Details) - Summary Financial Information of Myers Included in the Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 17,196	$ 22,843	$ 1,287	$ 1,872
Contracts receivable, including retainage	94,608	78,896
Other current assets	4,451us-gaap_OtherAssetsCurrent	5,278us-gaap_OtherAssetsCurrent
Total current assets	157,295us-gaap_AssetsCurrent	156,974us-gaap_AssetsCurrent
Property and equipment, net	82,541us-gaap_PropertyPlantAndEquipmentNet	87,098us-gaap_PropertyPlantAndEquipmentNet
Goodwill	54,820us-gaap_Goodwill	54,820us-gaap_Goodwill
Total assets	301,001us-gaap_Assets	306,451us-gaap_Assets
Current liabilities:
Accounts payable	71,462us-gaap_AccountsPayableCurrent	66,792us-gaap_AccountsPayableCurrent
Total current liabilities	120,242us-gaap_LiabilitiesCurrent	104,650us-gaap_LiabilitiesCurrent
Variable Interest Entity, Primary Beneficiary [Member]
Current assets:
Cash and cash equivalents	605	148
Contracts receivable, including retainage	28,889	21,327
Other current assets	6,986	7,656
Total current assets	36,480	29,131
Property and equipment, net	9,211	9,303
Goodwill	1,501	1,501
Total assets	47,192	39,935
Current liabilities:
Accounts payable	21,573	15,795
Other current liabilities	9,908	9,000
Total current liabilities	31,481	24,795
Long-term liabilities:
Other long-term liabilities	8	16
Total liabilities	$ 31,489	$ 24,811

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