Note 8 - Fair Value Measurements (Details) - The Carrying Values and Fair Values of These Notes Are as Follows (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
5 1/8% Senior Notes [Member]
Note 8 - Fair Value Measurements (Details) - The Carrying Values and Fair Values of These Notes Are as Follows [Line Items]
Carrying Value	$ 400,000	$ 400,000
Fair Value	419,000	405,752
6 1/2% Senior Notes [Member]
Note 8 - Fair Value Measurements (Details) - The Carrying Values and Fair Values of These Notes Are as Follows [Line Items]
Carrying Value	600,000	600,000
Fair Value	$ 623,250	$ 641,628

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 3: 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 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

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