Note 9 - Accumulated Other Comprehensive Income (Details) - Reconciliation of Net Income to Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Reconciliation of Net Income to Comprehensive Income [Abstract]
Net Income	$ 23,478	$ 15,179	$ 55,330	$ 34,358
Other comprehensive income, before tax:
Change in fair value of interest rate swaps	216	165	587	691
Change in fair value of available-for-sale securities			184
Unrealized gain on available-for-sale securities			150
Other comprehensive income, before tax	216	165	921	691
Income tax expense related to components of other comprehensive income	84	64	359	266
Other comprehensive income, net of tax	132	101	562	425
Comprehensive income	$ 23,610	$ 15,280	$ 55,892	$ 34,783

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount before tax, after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount before tax, after reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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