Note 1 - Summary of Significant Accounting Policies (Details) - Reclassified Balance Sheet Items (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Restricted cash and cash equivalents (current assets section)	$ 7,020	$ 10,298
Restricted cash and cash equivalents (other assets section)	3,631	3,631
Restricted marketable securities (current assets section)	19,805	14,027
Restricted marketable securities (other assets section)	138,468	127,976
Accounts receivable (current assets section)	78,843us-gaap_AccountsReceivableNetCurrent	79,856us-gaap_AccountsReceivableNetCurrent
Deposits and other assets (other assets section)	8,791us-gaap_DepositsAssetsNoncurrent	6,808us-gaap_DepositsAssetsNoncurrent
Accrued risk reserves (current liability section)	26,825us-gaap_SelfInsuranceReserveCurrent	24,325us-gaap_SelfInsuranceReserveCurrent
Accrued risk reserves (non-current liability section)	79,393us-gaap_SelfInsuranceReserveNoncurrent	86,232us-gaap_SelfInsuranceReserveNoncurrent
Deferred income taxes (other assets section)	18,700us-gaap_DeferredTaxAssetsNetNoncurrent	18,164us-gaap_DeferredTaxAssetsNetNoncurrent
Deferred income taxes (current liabilities section)	35,506us-gaap_DeferredTaxLiabilitiesCurrent	24,790us-gaap_DeferredTaxLiabilitiesCurrent
Scenario, Previously Reported [Member]
Restricted cash and cash equivalents (current assets section)		13,929
Restricted marketable securities (current assets section)		142,003
Accounts receivable (current assets section)		85,511
Deposits and other assets (other assets section)		1,153
Accrued risk reserves (current liability section)		110,557
Deferred income taxes (other assets section)		14,531
Deferred income taxes (current liabilities section)		21,157
Restatement Adjustment [Member]
Restricted cash and cash equivalents (current assets section)		(3,631)
Restricted cash and cash equivalents (other assets section)		3,631
Restricted marketable securities (current assets section)		(127,976)
Restricted marketable securities (other assets section)		127,976
Accounts receivable (current assets section)		(5,655)
Deposits and other assets (other assets section)		5,655
Accrued risk reserves (current liability section)		(86,232)
Accrued risk reserves (non-current liability section)		86,232
Deferred income taxes (other assets section)		3,633
Deferred income taxes (current liabilities section)		$ 3,633

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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