Note 3 - Business Acquisitions (Details) - Purchase Price Calculations - The Ryland Group, Inc. [Member] $ / shares in Units, shares in Thousands, $ in Thousands	Oct. 01, 2015 USD ($) $ / shares shares
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Number of shares of CalAtlantic common stock issued to Ryland shareholders (in Shares) | shares	47,989,812
Opening price per share of CalAtlantic common stock (in Dollars per share) | $ / shares	$ 40.46
Considerations	$ 30,600
Total purchase price	1,972,284
Common Stock [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Considerations	1,941,668
Equity Awards Exchanged for Acquisition Equity Awards [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Considerations	$ 30,616