Note 17 - Supplemental Guarantor Information - Supplemental Condensed Consolidating Statements of Operations (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Revenues:
Revenues	$ 98,960		$ 162,749	$ 230,993	$ 281,597
Cost of Sales:
Cost of Sales	106,211		145,295	226,577	251,132
Impairments	19,000		0	19,000	0
Gross Margin:
Gross margin	(7,251)		17,454	4,416	30,465
Selling and marketing expenses	(6,386)		(9,683)	(13,852)	(18,362)
General and administrative expenses	(6,892)		(5,841)	(12,915)	(13,232)
Equity in net income (loss) of unconsolidated joint ventures	(19,962)		185	(21,899)	369
Equity in net income (loss) of subsidiaries	0		0	0	0
Interest expense	(1,271)		0	(1,989)	0
Project abandonment costs	(94)	$ (14,000)	(14)	(14,130)	(19)
Gain on early extinguishment of debt	702		552	579	969
Other income (expense), net	(68)		(88)	155	(276)
Pretax income (loss)	(41,222)		2,565	(59,635)	(86)
(Provision) benefit for income taxes	16,929		(974)	26,866	(310)
Net loss	(24,293)		1,591	(32,769)	(396)
Net (income) loss attributable to non-controlling interest	0		(19)	0	(19)
Net income (loss) attributable to The New Home Company Inc.	(24,293)		1,572	(32,769)	(415)
Equity in net income of subsidiaries	0		0	0	0
Gain (Loss) on Extinguishment of Debt, Total	702		552	579	969
Other income (expense), net			(88)
Net income attributable to non-controlling interest	0		(19)	0	(19)
Consolidation, Eliminations [Member]
Revenues:
Revenues	0		0	0	0
Cost of Sales:
Cost of Sales	0		0	0	0
Gross Margin:
Gross margin	0		0	0	0
Selling and marketing expenses	0		0	0	0
General and administrative expenses	0		0	0	0
Equity in net income (loss) of unconsolidated joint ventures	0		0	0	0
Equity in net income (loss) of subsidiaries	25,858		(1,087)	36,388	625
Interest expense	0			0
Project abandonment costs	0		0	0	0
Gain on early extinguishment of debt	0		0	0	0
Other income (expense), net	0			0	0
Pretax income (loss)	25,858		(1,087)	36,388	625
(Provision) benefit for income taxes	0		0	0	0
Net loss	25,858		(1,087)	36,388	625
Net (income) loss attributable to non-controlling interest	0		0	0	0
Net income (loss) attributable to The New Home Company Inc.	25,858		(1,087)	36,388	625
Equity in net income of subsidiaries	25,858		(1,087)	36,388	625
Gain (Loss) on Extinguishment of Debt, Total	0		0	0	0
Other income (expense), net			0
Net income attributable to non-controlling interest	0		0	0	0
Parent Company [Member]
Revenues:
Revenues	0		0	0	0
Cost of Sales:
Cost of Sales	0		0	0	0
Gross Margin:
Gross margin	0		0	0	0
Selling and marketing expenses	0		0	0	0
General and administrative expenses	(960)		617	(739)	51
Equity in net income (loss) of unconsolidated joint ventures	0		0	0	0
Equity in net income (loss) of subsidiaries	(25,858)		1,087	(36,388)	(625)
Interest expense	0			0
Project abandonment costs	0		0	0	0
Gain on early extinguishment of debt	702		552	579	969
Other income (expense), net	(38)			155	(168)
Pretax income (loss)	(26,154)		2,150	(36,393)	227
(Provision) benefit for income taxes	1,861		(578)	3,624	(642)
Net loss	(24,293)		1,572	(32,769)	(415)
Net (income) loss attributable to non-controlling interest	0		0	0	0
Net income (loss) attributable to The New Home Company Inc.	(24,293)		1,572	(32,769)	(415)
Equity in net income of subsidiaries	(25,858)		1,087	(36,388)	(625)
Gain (Loss) on Extinguishment of Debt, Total	702		552	579	969
Other income (expense), net			(106)
Net income attributable to non-controlling interest	0		0	0	0
Guarantor Subsidiaries [Member]
Revenues:
Revenues	98,960		162,749	230,993	281,597
Cost of Sales:
Cost of Sales	106,211		145,352	226,577	251,189
Gross Margin:
Gross margin	(7,251)		17,397	4,416	30,408
Selling and marketing expenses	(6,386)		(9,683)	(13,852)	(18,362)
General and administrative expenses	(5,932)		(6,458)	(12,176)	(13,283)
Equity in net income (loss) of unconsolidated joint ventures	(19,962)		185	(21,899)	369
Equity in net income (loss) of subsidiaries	0		0	0	0
Interest expense	(1,271)			(1,989)
Project abandonment costs	(94)		(14)	(14,130)	(19)
Gain on early extinguishment of debt	0		0	0	0
Other income (expense), net	(30)			0	(108)
Pretax income (loss)	(40,926)		1,445	(59,630)	(995)
(Provision) benefit for income taxes	15,068		(396)	23,242	332
Net loss	(25,858)		1,049	(36,388)	(663)
Net (income) loss attributable to non-controlling interest	0		0	0	0
Net income (loss) attributable to The New Home Company Inc.	(25,858)		1,049	(36,388)	(663)
Equity in net income of subsidiaries	0		0	0	0
Gain (Loss) on Extinguishment of Debt, Total	0		0	0	0
Other income (expense), net			18
Net income attributable to non-controlling interest	0		0	0	0
Non-Guarantor Subsidiaries [Member]
Revenues:
Revenues	0		0	0	0
Cost of Sales:
Cost of Sales	0		(57)	0	(57)
Gross Margin:
Gross margin	0		57	0	57
Selling and marketing expenses	0		0	0	0
General and administrative expenses	0		0	0	0
Equity in net income (loss) of unconsolidated joint ventures	0		0	0	0
Equity in net income (loss) of subsidiaries	0		0	0	0
Interest expense	0			0
Project abandonment costs	0		0	0	0
Gain on early extinguishment of debt	0		0	0	0
Other income (expense), net	0			0	0
Pretax income (loss)	0		57	0	57
(Provision) benefit for income taxes	0		0	0	0
Net loss	0		57	0	57
Net (income) loss attributable to non-controlling interest	0		(19)	0	(19)
Net income (loss) attributable to The New Home Company Inc.	0		38	0	38
Equity in net income of subsidiaries	0		0	0	0
Gain (Loss) on Extinguishment of Debt, Total	0		0	0	0
Other income (expense), net			0
Net income attributable to non-controlling interest	0		(19)	0	(19)
Home Building [Member]
Revenues:
Revenues	77,757		140,464	173,416	239,650
Cost of Sales:
Cost of Sales	66,216		123,525	150,938	210,094
Impairments	19,000		0	19,000	0
Gross Margin:
Gross margin	(7,459)		16,939	3,478	29,556
Pretax income (loss)	(41,430)		2,050	(60,573)	(995)
Home Building [Member] | Consolidation, Eliminations [Member]
Revenues:
Revenues	0		0	0	0
Cost of Sales:
Cost of Sales	0		0	0	0
Impairments	0			0
Gross Margin:
Gross margin	0		0	0	0
Home Building [Member] | Parent Company [Member]
Revenues:
Revenues	0		0	0	0
Cost of Sales:
Cost of Sales	0		0	0	0
Impairments	0			0
Gross Margin:
Gross margin	0		0	0	0
Home Building [Member] | Guarantor Subsidiaries [Member]
Revenues:
Revenues	77,757		140,464	173,416	239,650
Cost of Sales:
Cost of Sales	66,216		123,582	150,938	210,151
Impairments	19,000			19,000
Gross Margin:
Gross margin	(7,459)		16,882	3,478	29,499
Home Building [Member] | Non-Guarantor Subsidiaries [Member]
Revenues:
Revenues	0		0	0	0
Cost of Sales:
Cost of Sales	0		(57)	0	(57)
Impairments	0			0
Gross Margin:
Gross margin	0		57	0	57
Land [Member]
Revenues:
Revenues	10		0	157	0
Cost of Sales:
Cost of Sales	10		0	157	0
Gross Margin:
Gross margin	0		0	0	0
Land [Member] | Consolidation, Eliminations [Member]
Revenues:
Revenues	0			0
Cost of Sales:
Cost of Sales	0			0
Gross Margin:
Gross margin	0			0
Land [Member] | Parent Company [Member]
Revenues:
Revenues	0			0
Cost of Sales:
Cost of Sales	0			0
Gross Margin:
Gross margin	0			0
Land [Member] | Guarantor Subsidiaries [Member]
Revenues:
Revenues	10			157
Cost of Sales:
Cost of Sales	10			157
Gross Margin:
Gross margin	0			0
Land [Member] | Non-Guarantor Subsidiaries [Member]
Revenues:
Revenues	0			0
Cost of Sales:
Cost of Sales	0			0
Gross Margin:
Gross margin	0			0
Construction [Member]
Revenues:
Revenues	21,193		22,285	57,420	41,947
Cost of Sales:
Cost of Sales	20,985		21,770	56,482	41,038
Gross Margin:
Gross margin	208		515	938	909
Pretax income (loss)	208		515	938	909
Construction [Member] | Consolidation, Eliminations [Member]
Revenues:
Revenues	0		0	0	0
Cost of Sales:
Cost of Sales	0		0	0	0
Gross Margin:
Gross margin	0		0	0	0
Construction [Member] | Parent Company [Member]
Revenues:
Revenues	0		0	0	0
Cost of Sales:
Cost of Sales	0		0	0	0
Gross Margin:
Gross margin	0		0	0	0
Construction [Member] | Guarantor Subsidiaries [Member]
Revenues:
Revenues	21,193		22,285	57,420	41,947
Cost of Sales:
Cost of Sales	20,985		21,770	56,482	41,038
Gross Margin:
Gross margin	208		515	938	909
Construction [Member] | Non-Guarantor Subsidiaries [Member]
Revenues:
Revenues	0		0	0	0
Cost of Sales:
Cost of Sales	0		0	0	0
Gross Margin:
Gross margin	$ 0		$ 0	$ 0	$ 0