Note 3 - Variable Interest Entities (Details) - Consolidated Balance Sheet-Myers (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 22,843	$ 1,872	$ 3,142	$ 16,371
Contracts receivable, including retainage	78,896	77,245
Other current assets	5,278us-gaap_OtherAssetsCurrent	11,377us-gaap_OtherAssetsCurrent
Total current assets	156,974us-gaap_AssetsCurrent	114,485us-gaap_AssetsCurrent
Property and equipment, net	87,098us-gaap_PropertyPlantAndEquipmentNet	93,683us-gaap_PropertyPlantAndEquipmentNet
Other assets, net	7,559us-gaap_OtherAssetsNoncurrent	10,030us-gaap_OtherAssetsNoncurrent
Goodwill	54,820us-gaap_Goodwill	54,820us-gaap_Goodwill		54,050us-gaap_Goodwill
Total assets	306,451us-gaap_Assets	273,018us-gaap_Assets
Current liabilities:
Accounts payable	66,792us-gaap_AccountsPayableCurrent	61,599us-gaap_AccountsPayableCurrent
Total current liabilities	104,650us-gaap_LiabilitiesCurrent	105,799us-gaap_LiabilitiesCurrent
Variable Interest Entity, Primary Beneficiary [Member]
Current assets:
Cash and cash equivalents	148	566
Contracts receivable, including retainage	21,327	6,475
Other current assets	7,656	7,964
Total current assets	29,131	15,005
Property and equipment, net	9,303	6,869
Other assets, net		5
Goodwill	1,501	1,501
Total assets	39,935	23,380
Current liabilities:
Accounts payable	15,795	8,361
Other current liabilities	9,000	7,080
Total current liabilities	24,795	15,441
Long-term liabilities:
Other long-term liabilities	16	137
Total liabilities	$ 24,811	$ 15,578

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