Note I - Long-term Debt (Details) - Long-term Debt (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Revolving Line of Credit/Swing Line. Outstanding borrowings bear daily interest at a base rate (based on the U.S. Prime Rate, which was 3.25% at December 31, 2014 and December 31, 2013, plus a spread) or LIBOR (1, 3, or 6 month rates) plus a spread, payable monthly	$ 350,052us-gaap_LongTermDebtNoncurrent	$ 40,000us-gaap_LongTermDebtNoncurrent
Line of Credit [Member]
Debt Instrument [Line Items]
Revolving Line of Credit/Swing Line. Outstanding borrowings bear daily interest at a base rate (based on the U.S. Prime Rate, which was 3.25% at December 31, 2014 and December 31, 2013, plus a spread) or LIBOR (1, 3, or 6 month rates) plus a spread, payable monthly	$ 350,052	$ 40,000

Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Name:	us-gaap_LongTermDebtNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant