Note 2 - Recently Issued Accounting Standards (Details Textual) - USD ($) $ in Thousands	3 Months Ended									12 Months Ended
	Dec. 31, 2019		Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019		Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2020	Jan. 01, 2019
Operating Lease, Right-of-Use Asset															$ 33,500
Operating Lease, Liability, Total	$ 32,170	[1]								$ 32,170	[1]				34,300
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest, Total	112,246		$ 62,806	$ 74,331	$ 55,606	$ 69,286	$ 67,420	$ 76,616	$ 50,532	304,989		$ 263,854	$ 229,732
Cumulative Effect of New Accounting Principle in Period of Adoption						(67)						(67)	1,774
Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption						(67)						(67)	5,766
Homebuilding Segment [Member]
Operating Lease, Right-of-Use Asset	30,277					0				30,277		0
Operating Lease, Liability, Total	$ 30,830					$ 0				30,830		0
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest, Total										244,762		$ 217,494	$ 185,939
Accounting Standards Update 2016-02 [Member] | Homebuilding Segment [Member]
Operating Lease, Right-of-Use Asset															34,200
Operating Lease, Liability, Total															$ 34,300
Accounting Standards Update 2016-01 [Member]
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest, Total										$ (1,600)
Accounting Standards Update 2016-13 [Member] | Retained Earnings [Member] | Subsequent Event [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption														$ 100

[1] Homebuilding and financial services operating lease liabilities of $30.8 million and $1.4 million, respectively, are included as a component of accrued and other liabilities and accrued liabilities, respectively, in the homebuilding and financial services section of our consolidated balance sheet at December 31, 2019.