Note 6 - Stockholders' Equity (Details) (Common Class A [Member], USD $) In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 11, 2012
Common Class A [Member]
Note 6 - Stockholders' Equity (Details) [Line Items]
Stock Repurchase Program, Authorized Amount		$ 100.0
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 86.7

Amount remaining of a stock repurchase plan authorized.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant