Note 2 - Restatement - Effects of Restatement (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								6 Months Ended		9 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	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash and cash equivalents	$ 262,273	$ 184,673	$ 144,958	$ 200,263	$ 272,804	$ 230,259	$ 195,515	$ 193,581	$ 144,958	$ 195,515	$ 184,673	$ 230,259	$ 262,273	$ 272,804	$ 233,711
Short-term marketable securities	27,799	37,918	41,037	36,049	30,002	35,010	20,014	39,961	41,037	20,014	37,918	35,010	27,799	30,002
Receivables, net	547,417	712,972	564,543	380,985	484,753	623,123	497,771	335,315	564,543	497,771	712,972	623,123	547,417	484,753
Contract assets	211,441	206,407	224,389	213,023	184,247	205,958	252,609	165,770	224,389	252,609	206,407	205,958	211,441	184,247
Inventories	88,885	95,442	101,686	96,862	88,623	90,789	96,024	71,295	101,686	96,024	95,442	90,789	88,885	88,623
Equity in construction joint ventures	193,110	203,954	220,247	219,908	231,365	234,716	215,093	200,310	220,247	215,093	203,954	234,716	193,110	231,365
Other current assets	46,016	51,925	80,560	62,755	48,710	32,185	47,293	46,122	80,560	47,293	51,925	32,185	46,016	48,710
Total current assets	1,376,941	1,493,291	1,377,420	1,209,845	1,340,504	1,515,028	1,324,319	1,052,354	1,377,420	1,324,319	1,493,291	1,515,028	1,376,941	1,340,504
Property and equipment, net	542,297	542,796	558,378	552,504	549,688	560,618	598,871	409,708	558,378	598,871	542,796	560,618	542,297	549,688
Long-term marketable securities	5,000	10,000	20,000	30,000	36,098	46,093	61,191	67,305	20,000	61,191	10,000	46,093	5,000	36,098
Investments in affiliates	84,176	84,914	82,109	81,034	84,354	84,840	91,695	38,682	82,109	91,695	84,914	84,840	84,176	84,354
Goodwill	264,279	264,112	264,107	259,695	259,471	244,696	254,058	53,799	264,107	254,058	264,112	244,696	264,279	259,471
Deferred income taxes, net	50,158	30,637	28,249	30,488	30,142	25,888	44,892	23,200	28,249	44,892	30,637	25,888	50,158	30,142
Other noncurrent assets	106,703	116,438	120,915	123,557	126,893	143,910	154,009	74,382	120,915	154,009	116,438	143,910	106,703	126,893
Segment assets	2,502,088	2,612,660	2,524,617	2,358,603	2,427,150	2,621,073	2,529,035	1,719,430	2,524,617	2,529,035	2,612,660	2,621,073	2,502,088	2,427,150
Current maturities of long-term debt	8,244	8,263	48,397	47,281	47,286	116,796	207,982	47,298	48,397	207,982	8,263	116,796	8,244	47,286
Accounts payable	400,775	399,743	302,651	216,150	256,757	316,917	303,885	227,091	302,651	303,885	399,743	316,917	400,775	256,757
Contract liabilities	95,737	109,299	128,443	104,260	109,011	118,986	92,657	70,962	128,443	92,657	109,299	118,986	95,737	109,011
Accrued expenses and other current liabilities	337,300	359,221	360,231	308,086	324,383	320,713	326,781	268,766	360,231	326,781	359,221	320,713	337,300	324,383
Total current liabilities	842,056	876,526	839,722	675,777	737,437	873,412	931,305	614,117	839,722	931,305	876,526	873,412	842,056	737,437
Long-term debt	356,108	394,841	366,896	333,290	335,119	316,926	280,710	176,011	366,896	280,710	394,841	316,926	356,108	335,119
Deferred income taxes, net	3,754	4,652	4,680	4,913	4,160	5,589	5,699	0	4,680	5,699	4,652	5,589	3,754	4,160
Other long-term liabilities	63,136	58,433	58,268	59,867	61,080	67,429	71,180	40,104	58,268	71,180	58,433	67,429	63,136	61,080
Commitments and contingencies
Preferred stock, $0.01 par value, authorized 3,000,000 shares, none outstanding	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Common stock, $0.01 par value, authorized 150,000,000 shares; issued and outstanding: 45,503,805 shares as of December 31, 2019 and 46,665,889 shares as of December 31, 2018	456	468	468	468	467	469	457	400	468	457	468	469	456	467
Additional paid-in capital	549,307	567,033	568,264	566,497	564,559	572,046	516,680	162,038	568,264	516,680	567,033	572,046	549,307	564,559
Accumulated other comprehensive loss	(2,645)	(3,282)	(2,187)	(1,081)	(749)	1,841	1,022	1,197	(2,187)	1,022	(3,282)	1,841	(2,645)	(749)
Retained earnings	594,353	619,690	579,920	610,302	679,453	738,254	676,572	676,705	579,920	676,572	619,690	738,254	594,353	679,453
Total Granite Construction Incorporated shareholders’ equity	1,141,471	1,183,909	1,146,465	1,176,186	1,243,730	1,312,610	1,194,731	840,340	1,146,465	1,194,731	1,183,909	1,312,610	1,141,471	1,243,730
Non-controlling interests	36,945	37,559	47,718	48,333	45,624	45,107	45,410	48,858	47,718	45,410	37,559	45,107	36,945	45,624
Total equity	1,178,416	1,221,468	1,194,183	1,224,519	1,289,354	1,357,717	1,240,141	889,198	1,194,183	1,240,141	1,221,468	1,357,717	1,178,416	1,289,354	921,147	$ 884,315
Total liabilities and equity	2,502,088	2,612,660	2,524,617	2,358,603	2,427,150	2,621,073	2,529,035	1,719,430	2,524,617	2,529,035	2,612,660	2,621,073	2,502,088	2,427,150
Total revenue	885,587	1,112,114	866,092	581,813	836,123	1,070,899	828,313	551,696					3,445,606	3,287,031	2,958,374
Total cost of revenue		989,556	819,334	580,675		910,238	728,889	507,432					3,223,928	2,952,191	2,679,633
Gross profit	51,224	122,558	46,758	1,138	30,491	160,661	99,424	44,264					221,678	334,840	278,741
Selling, general and administrative expenses		73,424	70,998	80,155		70,769	60,717	61,851					307,981	272,776	220,400
Acquisition and integration expenses		2,744	9,177	1,848		9,334	26,287	8,409					15,299	61,520	0
Gain on sales of property and equipment		(7,101)	(4,935)	(1,900)		(3,018)	(1,505)	(543)					(18,703)	(7,672)	(4,182)
Operating (loss) profit		53,491	(28,482)	(78,965)		83,576	13,925	(25,453)					(82,899)	8,216	62,523
Interest income		(1,713)	(1,728)	(2,816)		(1,533)	(1,173)	(1,521)					(7,433)	(6,082)	(4,742)
Interest expense		4,839	4,158	4,014		4,452	3,203	2,435					18,374	14,571	10,800
Equity in income of affiliates, net		(6,275)	(2,594)	(1,290)		(1,769)	(3,534)	(224)					(11,454)	(6,935)	(7,107)
Other income, net		127	(759)	(1,762)		(1,533)	(940)	268					(5,308)	(1,666)	(4,699)
Total other income		(3,022)	(923)	(1,854)		(383)	(2,444)	958					(5,821)	(112)	(5,748)
(Loss) income before benefit from income taxes		56,513	(27,559)	(77,111)		83,959	16,369	(26,411)					(77,078)	8,328	68,271
(Benefit from) provision for income taxes		11,747	(5,913)	(17,350)		12,698	7,599	(7,128)					(20,376)	(3,208)	25,814
Net (loss) income		44,766	(21,646)	(59,761)		71,261	8,770	(19,283)					(56,702)	11,536	42,457
Amount attributable to non-controlling interests		1,135	(2,596)	(2,709)		(3,425)	(2,904)	(1,161)					(3,489)	(10,954)	(8,341)
Net (loss) income attributable to Granite Construction Incorporated	$ (19,380)	$ 45,901	$ (24,242)	$ (62,470)	$ (52,676)	$ 67,836	$ 5,866	$ (20,444)					$ (60,191)	$ 582	$ 34,116
Basic (in dollars per share)	$ (0.42)	$ 0.98	$ (0.52)	$ (1.34)	$ (1.12)	$ 1.46	$ 0.14	$ (0.51)					$ (1.29)	$ 0.01	$ 0.86
Diluted (in dollars per share)	$ (0.42)	$ 0.97	$ (0.52)	$ (1.34)	$ (1.12)	$ 1.42	$ 0.14	$ (0.51)					$ (1.29)	$ 0.01	$ 0.84
Basic (in shares)		46,788	46,824	46,699		46,308	41,044	39,908					46,559	43,564	39,795
Diluted (in shares)		47,170	46,824	46,699		47,810	42,004	39,908					46,559	44,025	40,372
Net (loss) income	$ (20,061)	$ 44,766	$ (21,646)	$ (59,761)	$ (49,212)	$ 71,261	$ 8,770	$ (19,283)	(81,407)	(10,513)	(36,641)	60,748	$ (56,702)	$ 11,536	$ 42,457
Depreciation, depletion and amortization				29,055				15,511	61,747	43,547	92,700	77,816	123,418	111,544	66,345
Gain on sales of property and equipment, net				(1,900)				(543)	(6,835)	(2,048)	(13,936)	(5,066)	(18,703)	(4,910)	(4,182)
Change in deferred income taxes				0				0	(3)	0	(2,150)	(2,207)	(22,924)	12,110	(2,739)
Stock-based compensation				5,748				7,772	7,221	10,193	8,924	12,621	10,213	14,784	15,764
Equity in net loss from unconsolidated joint ventures				20,384				6,379	72,835	2,883	93,274	(6,245)	120,632	44,689	45,856
Net income from affiliates				(1,290)				0	(3,884)	(3,758)	(10,159)	(5,527)	(11,454)	(6,935)	(7,107)
Other non-cash adjustments				0					4,630		4,630		4,020	4,916	(939)
Receivables				103,484				58,457	(79,090)	(24,821)	(225,558)	(154,996)	(58,947)	(9,247)	(65,750)
Contract assets, net				(33,345)				(44,813)	(20,426)	(72,653)	(21,539)	(249)	(40,084)	11,384	0
Inventories				(8,238)				(8,798)	(12,329)	(9,526)	(6,178)	(4,283)	380	(2,120)	(7,252)
Contributions to unconsolidated construction joint ventures				(26,933)				(26,067)	(45,500)	(55,733)	(57,280)	(89,000)	(83,765)	(104,333)	(16,937)
Distributions from unconsolidated construction joint ventures and affiliates				330				4,036	830	11,201	13,181	15,581	19,064	16,922	39,955
Other assets, net				(11,648)				(9,133)	(32,785)	5,998	(10,390)	30,728	(3,928)	21,619	13,586
Accounts payable				(40,588)				(12,000)	42,477	24,559	143,678	41,672	140,027	(21,456)	37,692
Accrued expenses and other current liabilities, net				(11,662)				(9,138)	(996)	5,226	946	43,150	(9,809)	(14,113)	11,053
Net cash used in operating activities				(36,364)				(37,620)	(93,515)	(75,445)	(26,498)	14,743	111,438	86,390	146,195
Costs and estimated earnings in excess of billings, net													0	0	(21,607)
Accounting Standards Update 2016-02 [Member]
Retained earnings	$ (500)												(500)
Previously Reported [Member]
Cash and cash equivalents		184,673	144,958	200,263	272,804	230,259	195,515	193,581	144,958	195,515	184,673	230,259		272,804
Short-term marketable securities		37,918	41,037	36,049	30,002	35,010	20,014	39,961	41,037	20,014	37,918	35,010		30,002
Receivables, net		700,387	551,958	368,215	473,246	618,070	492,718	330,192	551,958	492,718	700,387	618,070		473,246
Contract assets		233,925	257,650	260,250	219,754	213,989	265,190	178,663	257,650	265,190	233,925	213,989		219,754
Inventories		95,442	102,163	96,862	88,623	90,789	96,024	71,295	102,163	96,024	95,442	90,789		88,623
Equity in construction joint ventures		209,765	241,786	300,489	282,229	273,993	252,467	254,816	241,786	252,467	209,765	273,993		282,229
Other current assets		42,698	63,056	54,590	48,731	32,185	49,100	43,125	63,056	49,100	42,698	32,185		48,731
Total current assets		1,504,808	1,402,608	1,316,718	1,415,389	1,557,283	1,371,028	1,111,633	1,402,608	1,371,028	1,504,808	1,557,283		1,415,389
Property and equipment, net		542,796	557,118	552,504	549,688	560,618	595,787	409,708	557,118	595,787	542,796	560,618		549,688
Long-term marketable securities		10,000	20,000	30,000	36,098	46,093	61,191	67,305	20,000	61,191	10,000	46,093		36,098
Investments in affiliates		84,914	82,109	81,034	84,354	84,840	99,495	38,682	82,109	99,495	84,914	84,840		84,354
Goodwill		264,112	264,107	259,695	259,471	244,696	246,881	53,799	264,107	246,881	264,112	244,696		259,471
Deferred income taxes, net		38,443	36,055	0	2,918	6,408	25,135	3,718	36,055	25,135	38,443	6,408		2,918
Other noncurrent assets		118,228	122,705	128,349	128,683	143,910	156,808	74,382	122,705	156,808	118,228	143,910		128,683
Segment assets		2,633,773	2,558,141	2,439,780	2,476,601	2,643,848	2,556,325	1,759,227	2,558,141	2,556,325	2,633,773	2,643,848		2,476,601
Current maturities of long-term debt		8,263	48,397	47,281	47,286	116,796	207,982	47,298	48,397	207,982	8,263	116,796		47,286
Accounts payable		399,528	303,128	216,966	251,481	316,917	303,885	226,253	303,128	303,885	399,528	316,917		251,481
Contract liabilities		106,010	119,289	90,752	105,449	117,759	91,864	71,030	119,289	91,864	106,010	117,759		105,449
Accrued expenses and other current liabilities		342,040	339,047	265,102	273,626	296,033	293,959	233,637	339,047	293,959	342,040	296,033		273,626
Total current liabilities		855,841	809,861	620,101	677,842	847,505	897,690	578,218	809,861	897,690	855,841	847,505		677,842
Long-term debt		394,841	366,896	333,290	335,119	316,926	280,710	176,011	366,896	280,710	394,841	316,926		335,119
Deferred income taxes, net		4,652	4,680	0	4,317	5,589	5,759	0	4,680	5,759	4,652	5,589		4,317
Other long-term liabilities		58,433	58,268	64,219	61,689	67,429	71,180	40,104	58,268	71,180	58,433	67,429		61,689
Preferred stock, $0.01 par value, authorized 3,000,000 shares, none outstanding		0	0	0	0	0	0	0	0	0	0	0		0
Common stock, $0.01 par value, authorized 150,000,000 shares; issued and outstanding: 45,503,805 shares as of December 31, 2019 and 46,665,889 shares as of December 31, 2018		468	468	468	467	469	457	400	468	457	468	469		467
Additional paid-in capital		567,033	568,264	566,497	564,559	572,046	516,680	162,038	568,264	516,680	567,033	572,046		564,559
Accumulated other comprehensive loss		(3,282)	(3,448)	(626)	(749)	1,841	1,022	1,197	(3,448)	1,022	(3,282)	1,841		(749)
Retained earnings		656,487	642,124	746,100	787,356	786,936	737,417	751,801	642,124	737,417	656,487	786,936		787,356
Total Granite Construction Incorporated shareholders’ equity		1,220,706	1,207,408	1,312,439	1,351,633	1,361,292	1,255,576	915,436	1,207,408	1,255,576	1,220,706	1,361,292		1,351,633
Non-controlling interests		42,560	50,160	49,494	46,001	45,107	45,410	49,458	50,160	45,410	42,560	45,107		46,001
Total equity		1,263,266	1,257,568	1,361,933	1,397,634	1,406,399	1,300,986	964,894	1,257,568	1,300,986	1,263,266	1,406,399		1,397,634
Total liabilities and equity		2,633,773	2,558,141	2,439,780	2,476,601	2,643,848	2,556,325	1,759,227	2,558,141	2,556,325	2,633,773	2,643,848		2,476,601
Total revenue		1,088,110	789,540	619,801		1,055,591	807,119	563,379						3,318,414	2,989,713
Total cost of revenue		996,678	841,944	579,323		911,100	726,750	507,096						2,929,222	2,674,780
Gross profit		91,432	(52,404)	40,478		144,491	80,369	56,283						389,192	314,933
Selling, general and administrative expenses		73,424	69,998	81,155		70,769	61,316	61,252						272,776	220,400
Acquisition and integration expenses		2,744	9,177	3,323		9,334	26,287	8,409						60,045
Gain on sales of property and equipment		(7,101)	(4,935)	(1,900)		(3,018)	(1,505)	(543)						(7,672)	(4,182)
Operating (loss) profit		22,365	(126,644)	(42,100)		67,406	(5,729)	(12,835)						64,043	98,715
Interest income		(1,713)	(1,728)	(2,816)		(1,533)	(1,173)	(1,521)						(6,082)	(4,742)
Interest expense		4,839	4,158	4,014		4,452	3,203	2,435						14,571	10,800
Equity in income of affiliates, net		(6,275)	(2,594)	(1,290)		(1,769)	(3,534)	(224)						(6,935)	(7,107)
Other income, net		127	(759)	(1,762)		(1,533)	(940)	268						(1,666)	(4,699)
Total other income		(3,022)	(923)	(1,854)		(383)	(2,444)	958						(112)	(5,748)
(Loss) income before benefit from income taxes		25,387	(125,721)	(40,246)		67,789	(3,285)	(13,793)						64,155	104,463
(Benefit from) provision for income taxes		3,474	(31,760)	(9,165)		8,692	2,796	(4,131)						10,414	28,662
Net (loss) income		21,913	(93,961)	(31,081)		59,097	(6,081)	(9,662)						53,741	75,801
Amount attributable to non-controlling interests		(1,425)	(3,875)	(3,493)		(3,425)	(2,304)	(1,761)						(11,331)	(6,703)
Net (loss) income attributable to Granite Construction Incorporated		$ 20,488	$ (97,836)	$ (34,574)		$ 55,672	$ (8,385)	$ (11,423)						$ 42,410	$ 69,098
Basic (in dollars per share)		$ 0.44	$ (2.09)	$ (0.74)		$ 1.20	$ (0.20)	$ (0.29)						$ 0.97	$ 1.74
Diluted (in dollars per share)		$ 0.43	$ (2.09)	$ (0.74)		$ 1.17	$ (0.20)	$ (0.29)						$ 0.96	$ 1.71
Basic (in shares)		46,788	46,824	46,699		46,308	41,044	39,908						43,564	39,795
Diluted (in shares)		47,170	46,824	46,699		47,810	41,044	39,908						44,025	40,372
Net (loss) income				$ (31,081)				$ (9,662)	(125,042)	(15,743)	(103,129)	43,354		$ 53,741	$ 75,801
Depreciation, depletion and amortization				28,846				15,511	61,747	43,547	92,700	77,816		111,544	66,345
Gain on sales of property and equipment, net				(1,900)				(543)	(6,835)	(2,048)	(13,936)	(5,066)		(4,910)	(4,182)
Change in deferred income taxes				0				0	(35,192)	0	(37,338)	(2,207)		20,010	(4,824)
Stock-based compensation				5,748				7,772	7,221	10,193	8,924	12,621		14,784	15,764
Equity in net loss from unconsolidated joint ventures				(455)				(2,637)	105,834	13,418	173,008	16,343		22,688	14,634
Net income from affiliates				0				0	(3,884)	(3,758)	(10,159)	(5,527)		(6,935)	(7,107)
Other non-cash adjustments				0					4,630		4,630			4,916	0
Receivables				105,086				58,527	(78,081)	(24,821)	(224,475)	(154,996)		(4,584)	(60,272)
Contract assets, net				(55,550)				(47,777)	(23,775)	(76,166)	(13,276)	355		(17,770)
Inventories				(8,238)				(8,798)	(12,905)	(9,526)	(6,178)	(4,283)		(2,120)	(7,252)
Contributions to unconsolidated construction joint ventures				(26,933)				(26,067)	(45,500)	(55,733)	(57,280)	(89,000)		(104,333)	(16,937)
Distributions from unconsolidated construction joint ventures and affiliates				330				4,036	830	11,201	13,181	15,581		16,922	39,955
Other assets, net				(4,189)				(6,136)	(15,361)	4,192	(1,141)	30,728		21,598	12,272
Accounts payable				(34,110)				(12,838)	48,230	24,559	148,739	41,672		(26,732)	36,716
Accrued expenses and other current liabilities, net				(13,918)				(9,008)	24,568	5,240	(768)	37,352		(12,429)	11,348
Net cash used in operating activities				(36,364)				(37,620)	(93,515)	(75,445)	(26,498)	14,743		86,390	146,195
Costs and estimated earnings in excess of billings, net															(26,066)
Revision of Prior Period, Error Correction, Adjustment [Member]
Cash and cash equivalents		$ 0	$ 0	0	0	$ 0	$ 0	0	0	0	0	0		0
Short-term marketable securities		0	0	0	0	0	0	0	0	0	0	0		0
Receivables, net		10,569	10,567	10,566	10,567	4,491	4,491	4,491	10,567	4,491	10,569	4,491		10,567
Contract assets		(17,452)	(30,286)	(45,011)	(35,094)	(8,515)	(13,005)	(8,766)	(30,286)	(13,005)	(17,452)	(8,515)		(35,094)
Inventories		0	0	0	0	0	0	0	0	0	0	0		0
Equity in construction joint ventures		(10,351)	(18,401)	(74,557)	(47,799)	(38,249)	(36,347)	(54,506)	(18,401)	(36,347)	(10,351)	(38,249)		(47,799)
Other current assets		9,019	16,919	7,606	(21)	0	(1,891)	2,499	16,919	(1,891)	9,019	0		(21)
Total current assets		(8,215)	(21,201)	(101,396)	(72,347)	(42,273)	(46,752)	(56,282)	(21,201)	(46,752)	(8,215)	(42,273)		(72,347)
Property and equipment, net		0	0	0	0	0	0	0	0	0	0	0		0
Long-term marketable securities		0	0	0	0	0	0	0	0	0	0	0		0
Investments in affiliates		0	0	0	0	0	0	0	0	0	0	0		0
Goodwill		0	0	0	0	0	0	0	0	0	0	0		0
Deferred income taxes, net		(8,580)	(8,580)	26,608	26,607	19,480	19,480	19,480	(8,580)	19,480	(8,580)	19,480		26,607
Other noncurrent assets		0	0	0	0	0	0	0	0	0	0	0		0
Segment assets		(16,795)	(29,781)	(74,788)	(45,740)	(22,793)	(27,272)	(36,802)	(29,781)	(27,272)	(16,795)	(22,793)		(45,740)
Current maturities of long-term debt		0	0	0	0	0	0	0	0	0	0	0		0
Accounts payable		0	0	0	0	0	0	0	0	0	0	0		0
Contract liabilities		9,025	9,154	14,561	7,957	1,901	(544)	1,013	9,154	(544)	9,025	1,901		7,957
Accrued expenses and other current liabilities		12,031	21,184	43,035	51,916	24,260	32,822	35,263	21,184	32,822	12,031	24,260		51,916
Total current liabilities		21,056	30,338	57,596	59,873	26,161	32,278	36,276	30,338	32,278	21,056	26,161		59,873
Long-term debt		0	0	0	0	0	0	0	0	0	0	0		0
Deferred income taxes, net		0	0	0	0	0	0	0	0	0	0	0		0
Other long-term liabilities		0	0	0	0	0	0	0	0	0	0	0		0
Preferred stock, $0.01 par value, authorized 3,000,000 shares, none outstanding		0	0	0	0	0	0	0	0	0	0	0		0
Common stock, $0.01 par value, authorized 150,000,000 shares; issued and outstanding: 45,503,805 shares as of December 31, 2019 and 46,665,889 shares as of December 31, 2018		0	0	0	0	0	0	0	0	0	0	0		0
Additional paid-in capital		0	0	0	0	0	0	0	0	0	0	0		0
Accumulated other comprehensive loss		0	0	0	0	0	0	0	0	0	0	0		0
Retained earnings		(34,046)	(58,719)	(132,325)	(105,613)	(48,954)	(59,550)	(73,078)	(58,719)	(59,550)	(34,046)	(48,954)		(105,613)
Total Granite Construction Incorporated shareholders’ equity		(34,046)	(58,719)	(132,325)	(105,613)	(48,954)	(59,550)	(73,078)	(58,719)	(59,550)	(34,046)	(48,954)		(105,613)
Non-controlling interests		(3,805)	(1,400)	(59)	0	0	0	0	(1,400)	0	(3,805)	0		0
Total equity		(37,851)	(60,119)	(132,384)	(105,613)	(48,954)	(59,550)	(73,078)	(60,119)	(59,550)	(37,851)	(48,954)		(105,613)
Total liabilities and equity		(16,795)	(29,781)	(74,788)	(45,740)	(22,793)	(27,272)	(36,802)	(29,781)	(27,272)	(16,795)	(22,793)		(45,740)
Total revenue		22,090	75,527	(28,192)		10,087	20,092	(10,221)						(35,627)	(35,153)
Total cost of revenue		(7,571)	(22,610)	6,208		(4,012)	2,173	302						18,113	4,338
Gross profit		29,661	98,137	(34,400)		14,099	17,919	(10,523)						(53,740)	(39,491)
Selling, general and administrative expenses						0	0	0
Acquisition and integration expenses		0	0			0	0	0						0
Gain on sales of property and equipment		0	0	0		0	0	0						0	0
Operating (loss) profit		29,661	98,137	(34,400)		14,099	17,919	(10,523)						(53,740)	(39,491)
Interest income		0	0	0		0	0	0						0	0
Interest expense		0	0	0		0	0	0						0	0
Equity in income of affiliates, net		0	0	0		0	0	0						0	0
Other income, net		0	0	0		0	0	0						0	0
Total other income		0	0	0		0	0	0						0	0
(Loss) income before benefit from income taxes		29,661	98,137	(34,400)		14,099	17,919	(10,523)						(53,740)	(39,491)
(Benefit from) provision for income taxes		7,898	25,874	(7,627)		3,502	4,390	(2,500)						(13,182)	(3,537)
Net (loss) income		21,763	72,263	(26,773)		10,597	13,529	(8,023)						(40,558)	(35,954)
Amount attributable to non-controlling interests		2,660	1,341	59		0	0	0						0	0
Net (loss) income attributable to Granite Construction Incorporated		$ 24,423	$ 73,604	$ (26,714)		$ 10,597	$ 13,529	$ (8,023)						$ (40,558)	$ (35,954)
Basic (in dollars per share)		$ 0.52	$ 1.57	$ (0.57)		$ 0.23	$ 0.33	$ (0.20)						$ (0.93)	$ (0.90)
Diluted (in dollars per share)		$ 0.52	$ 1.57	$ (0.57)		$ 0.22	$ 0.33	$ (0.20)						$ (0.92)	$ (0.89)
Basic (in shares)		46,788	46,824	46,699		46,308	41,044	39,908						43,564	39,795
Diluted (in shares)		47,170	46,824	46,699		47,810	41,044	39,908						44,025	40,372
Net (loss) income				$ (26,773)				$ (8,023)	45,490	5,505	67,253	16,101		$ (40,558)	$ (35,954)
Depreciation, depletion and amortization				0				0	0	0	0	0		0	0
Gain on sales of property and equipment, net				0				0	0	0	0	0		0	0
Change in deferred income taxes				0				0	35,189	0	35,188	0		(7,127)	954
Stock-based compensation				0				0	0	0	0	0		0	0
Equity in net loss from unconsolidated joint ventures				17,879				9,016	(60,073)	(11,560)	(77,334)	(23,631)		18,967	31,222
Net income from affiliates				0				0	0	0	0	0		0	0
Other non-cash adjustments				0					0		0			0	0
Receivables				0				0	0	0	0	0		(6,075)	(4,492)
Contract assets, net				16,479				1,506	(3,687)	4,164	(16,109)	2,138		34,772
Inventories				0				0	0	0	0	0		0	0
Contributions to unconsolidated construction joint ventures				0				0	0	0	0	0		0	0
Distributions from unconsolidated construction joint ventures and affiliates				0				0	0	0	0	0		0	0
Other assets, net				(7,585)				(2,499)	(16,919)	1,891	(8,998)	0		21	0
Accounts payable				0				0	0	0	0	0		0	0
Accrued expenses and other current liabilities, net				0				0	0	0	0	5,392		0	0
Net cash used in operating activities				0				0	0	0	0	0		0	0
Costs and estimated earnings in excess of billings, net															8,270
Revision of Prior Period, Adjustment [Member]
Cash and cash equivalents		$ 0	$ 0	0	0	$ 0	$ 0	0	0	0	0	0		0
Short-term marketable securities		0	0	0	0	0	0	0	0	0	0	0		0
Receivables, net		2,016	2,018	2,204	940	562	562	632	2,018	562	2,016	562		940
Contract assets		(10,066)	(2,975)	(2,216)	(413)	484	424	(4,127)	(2,975)	424	(10,066)	484		(413)
Inventories		0	(477)	0	0	0	0	0	(477)	0	0	0		0
Equity in construction joint ventures		4,540	(3,138)	(6,024)	(3,065)	(1,028)	(1,027)	0	(3,138)	(1,027)	4,540	(1,028)		(3,065)
Other current assets		208	585	559	0	0	84	498	585	84	208	0		0
Total current assets		(3,302)	(3,987)	(5,477)	(2,538)	18	43	(2,997)	(3,987)	43	(3,302)	18		(2,538)
Property and equipment, net		0	1,260	0	0	0	3,084	0	1,260	3,084	0	0		0
Long-term marketable securities		0	0	0	0	0	0	0	0	0	0	0		0
Investments in affiliates		0	0	0	0	0	(7,800)	0	0	(7,800)	0	0		0
Goodwill		0	0	0	0	0	7,177	0	0	7,177	0	0		0
Deferred income taxes, net		774	774	3,880	617	0	277	2	774	277	774	0		617
Other noncurrent assets		(1,790)	(1,790)	(4,792)	(1,790)	0	(2,799)	0	(1,790)	(2,799)	(1,790)	0		(1,790)
Segment assets		(4,318)	(3,743)	(6,389)	(3,711)	18	(18)	(2,995)	(3,743)	(18)	(4,318)	18		(3,711)
Current maturities of long-term debt		0	0	0	0	0	0	0	0	0	0	0		0
Accounts payable		215	(477)	(816)	5,276	0	0	838	(477)	0	215	0		5,276
Contract liabilities		(5,736)	0	(1,053)	(4,395)	(674)	1,337	(1,081)	0	1,337	(5,736)	(674)		(4,395)
Accrued expenses and other current liabilities		5,150	0	(51)	(1,159)	420	0	(134)	0	0	5,150	420		(1,159)
Total current liabilities		(371)	(477)	(1,920)	(278)	(254)	1,337	(377)	(477)	1,337	(371)	(254)		(278)
Long-term debt		0	0	0	0	0	0	0	0	0	0	0		0
Deferred income taxes, net		0	0	4,913	(157)	0	(60)	0	0	(60)	0	0		(157)
Other long-term liabilities		0	0	(4,352)	(609)	0	0	0	0	0	0	0		(609)
Preferred stock, $0.01 par value, authorized 3,000,000 shares, none outstanding		0	0	0	0	0	0	0	0	0	0	0		0
Common stock, $0.01 par value, authorized 150,000,000 shares; issued and outstanding: 45,503,805 shares as of December 31, 2019 and 46,665,889 shares as of December 31, 2018		0	0	0	0	0	0	0	0	0	0	0		0
Additional paid-in capital		0	0	0	0	0	0	0	0	0	0	0		0
Accumulated other comprehensive loss		0	1,261	(455)	0	0	0	0	1,261	0	0	0		0
Retained earnings		(2,751)	(3,485)	(3,473)	(2,290)	272	(1,295)	(2,018)	(3,485)	(1,295)	(2,751)	272		(2,290)
Total Granite Construction Incorporated shareholders’ equity		(2,751)	(2,224)	(3,928)	(2,290)	272	(1,295)	(2,018)	(2,224)	(1,295)	(2,751)	272		(2,290)
Non-controlling interests		(1,196)	(1,042)	(1,102)	(377)	0	0	(600)	(1,042)	0	(1,196)	0		(377)
Total equity		(3,947)	(3,266)	(5,030)	(2,667)	272	(1,295)	(2,618)	(3,266)	(1,295)	(3,947)	272		(2,667)
Total liabilities and equity		(4,318)	(3,743)	(6,389)	$ (3,711)	18	(18)	(2,995)	(3,743)	(18)	(4,318)	18		(3,711)
Total revenue		1,914	1,025	(9,796)		5,221	1,102	(1,462)						4,244	3,814
Total cost of revenue		449		(4,856)		3,150	(34)	34						4,856	515
Gross profit		1,465	1,025	(4,940)		2,071	1,136	(1,496)						(612)	3,299
Selling, general and administrative expenses			1,000	(1,000)		0	(599)	599
Acquisition and integration expenses		0	0	(1,475)		0	0	0						1,475
Gain on sales of property and equipment		0	0	0		0	0	0						0	0
Operating (loss) profit		1,465	25	(2,465)		2,071	1,735	(2,095)						(2,087)	3,299
Interest income		0	0	0		0	0	0						0	0
Interest expense		0	0	0		0	0	0						0	0
Equity in income of affiliates, net		0	0	0		0	0	0						0	0
Other income, net		0	0	0		0	0	0						0	0
Total other income		0	0	0		0	0	0						0	0
(Loss) income before benefit from income taxes		1,465	25	(2,465)		2,071	1,735	(2,095)						(2,087)	3,299
(Benefit from) provision for income taxes		375	(27)	(558)		504	413	(497)						(440)	689
Net (loss) income		1,090	52	(1,907)		1,567	1,322	(1,598)						(1,647)	2,610
Amount attributable to non-controlling interests		(100)	(62)	725		0	(600)	600						377	(1,638)
Net (loss) income attributable to Granite Construction Incorporated		$ 990	$ (10)	$ (1,182)		$ 1,567	$ 722	$ (998)						$ (1,270)	$ 972
Basic (in dollars per share)		$ 0.02	$ (0.00)	$ (0.03)		$ 0.03	$ 0.01	$ (0.02)						$ (0.03)	$ 0.02
Diluted (in dollars per share)		$ 0.02	$ (0.00)	$ (0.03)		$ 0.03	$ 0.01	$ (0.02)						$ (0.03)	$ 0.02
Basic (in shares)		46,788	46,824	46,699		46,308	41,044	39,908						43,564	39,795
Diluted (in shares)		47,170	46,824	46,699		47,810	41,044	39,908						44,025	40,372
Net (loss) income				$ (1,907)				$ (1,598)	(1,855)	(275)	(765)	1,293		$ (1,647)	$ 2,610
Depreciation, depletion and amortization				209				0	0	0	0	0		0	0
Gain on sales of property and equipment, net				0				0	0	0	0	0		0	0
Change in deferred income taxes				0				0	0	0	0	0		(773)	1,131
Stock-based compensation				0				0	0	0	0	0		0	0
Equity in net loss from unconsolidated joint ventures				2,960				0	27,074	1,025	(2,400)	1,043		3,034	0
Net income from affiliates				(1,290)				0	0	0	0	0		0	0
Other non-cash adjustments				0					0		0			0	(939)
Receivables				(1,602)				(70)	(1,009)	0	(1,083)	0		1,412	(986)
Contract assets, net				5,726				1,458	7,036	(651)	7,846	(2,742)		(5,618)
Inventories				0				0	576	0	0	0		0	0
Contributions to unconsolidated construction joint ventures				0				0	0	0	0	0		0	0
Distributions from unconsolidated construction joint ventures and affiliates				0				0	0	0	0	0		0	0
Other assets, net				126				(498)	(505)	(85)	(251)	0		0	1,314
Accounts payable				(6,478)				838	(5,753)	0	(5,061)	0		5,276	976
Accrued expenses and other current liabilities, net				2,256				(130)	(25,564)	(14)	1,714	406		(1,684)	(295)
Net cash used in operating activities				0				0	$ 0	$ 0	$ 0	$ 0		0	0
Costs and estimated earnings in excess of billings, net															(3,811)
Transportation [Member]
Total revenue		$ 623,867	$ 481,746	301,964		$ 622,895	$ 523,900	347,566					1,892,149	1,946,750	1,912,006
Total cost of revenue		577,002	481,247	318,312		535,859	469,661	327,246					1,837,148	1,809,664	1,782,138
Transportation [Member] | Previously Reported [Member]
Total revenue		598,646	403,978	338,210		610,847	502,711	359,145						1,976,743	1,947,420
Total cost of revenue		585,013	503,857	316,960		539,871	466,748	327,683						1,786,698	1,777,285
Transportation [Member] | Revision of Prior Period, Error Correction, Adjustment [Member]
Total revenue		23,861	76,255	(28,022)		10,204	20,227	(10,113)						(35,154)	(34,427)
Total cost of revenue		(8,245)	(22,610)	6,208		(4,012)	2,173	302						18,113
Transportation [Member] | Revision of Prior Period, Error Correction, Adjustment [Member] | Accounting Standards Update 2016-02 [Member]
Total cost of revenue															4,338
Transportation [Member] | Revision of Prior Period, Adjustment [Member]
Total revenue		1,360	1,513	(8,224)		1,844	962	(1,466)						5,161	(987)
Total cost of revenue		234	0	(4,856)		0	740	(739)						4,853	515
Water [Member]
Total revenue		134,404	112,070	99,082		127,971	51,379	39,937					468,730	345,861	132,973
Total cost of revenue		121,767	101,568	91,136		103,966	45,295	29,250					438,964	286,727	121,429
Water [Member] | Previously Reported [Member]
Total revenue		135,908	112,831	99,255		124,292	51,618	40,041						338,250	133,699
Total cost of revenue		120,878	101,568	91,136		100,189	46,168	28,477						278,676	121,429
Water [Member] | Revision of Prior Period, Error Correction, Adjustment [Member]
Total revenue		(1,771)	(728)	(170)		(117)	(135)	(108)						(473)	(726)
Total cost of revenue		674				0	0	0
Water [Member] | Revision of Prior Period, Adjustment [Member]
Total revenue		267	(33)	(3)		3,796	(104)	4						8,084	0
Total cost of revenue		215				3,777	(873)	773						8,051
Specialty [Member]
Total revenue		224,744	174,629	139,124		190,944	152,086	118,471					727,537	625,666	620,619
Total cost of revenue		186,158	152,874	125,826		162,638	130,465	102,735					640,808	535,731	528,372
Specialty [Member] | Previously Reported [Member]
Total revenue		224,457	175,084	140,693		190,836	151,842	118,471						626,619	615,818
Total cost of revenue		186,158	152,874	125,826		162,737	130,366	102,735						535,731	528,372
Specialty [Member] | Revision of Prior Period, Error Correction, Adjustment [Member]
Total revenue		0	0	0		0	0	0						0	0
Total cost of revenue						0	0	0
Specialty [Member] | Revision of Prior Period, Adjustment [Member]
Total revenue		287	(455)	(1,569)		108	244	0						(953)	4,801
Total cost of revenue						(99)	99	0
Materials [Member]
Total revenue		129,099	97,647	41,643		129,089	100,948	45,722					357,190	368,754	292,776
Total cost of revenue		104,629	83,645	45,401		107,775	83,468	48,201					$ 307,008	320,069	247,694
Materials [Member] | Previously Reported [Member]
Total revenue		129,099	97,647	41,643		129,616	100,948	45,722						376,802	292,776
Total cost of revenue		104,629	83,645	45,401		108,303	83,468	48,201						328,117	247,694
Materials [Member] | Revision of Prior Period, Error Correction, Adjustment [Member]
Total revenue		0	0	0		0	0	0						0	0
Total cost of revenue						0	0	0
Materials [Member] | Revision of Prior Period, Adjustment [Member]
Total revenue		$ 0	$ 0	$ 0		(527)	0	0						(8,048)	$ 0
Total cost of revenue						$ (528)	$ 0	$ 0						$ (8,048)