Construction and Line Item Joint Ventures - Consolidated Construction Joint Ventures (Details) (USD $)	3 Months Ended				6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011		Jun. 30, 2012		Jun. 30, 2011		Dec. 31, 2011		Dec. 31, 2010
Construction Joint Venture [Line Items]
Cash and cash equivalents	$ 237,951,000		$ 190,069,000		$ 237,951,000		$ 190,069,000		$ 256,990,000		$ 252,022,000
Other current assets	20,436,000		34,779,000		20,436,000		34,779,000		35,171,000
Total current assets	915,159,000		922,605,000		915,159,000		922,605,000		909,722,000
Other noncurrent assets	78,503,000		82,214,000		78,503,000		82,214,000		80,616,000
Total assets	1,507,647,000		1,551,947,000		1,507,647,000		1,551,947,000		1,547,799,000
Accounts payable	186,290,000		179,664,000		186,290,000		179,664,000		158,660,000
Billings in excess of costs and estimated earnings	75,629,000		122,014,000		75,629,000		122,014,000		90,845,000
Accrued expenses and other current liabilities	155,322,000		156,727,000		155,322,000		156,727,000		166,790,000
Total current liabilities	442,671,000		483,210,000		442,671,000		483,210,000		448,468,000
Construction	245,113,000		260,600,000		363,059,000		353,292,000
Net Cash Provided by (Used in) Operating Activities					(34,624,000)		(16,736,000)
Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Number of Active Joint Venture Projects	4				4
Partnership Interest [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	1,900,000,000				1,900,000,000
Joint Venture Consolidated [Member] | Consolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Cash and cash equivalents	67,685,000	[1]	89,666,000	[1]	67,685,000	[1]	89,666,000	[1]	75,122,000	[1]
Other current assets	29,028,000		35,183,000		29,028,000		35,183,000		33,750,000
Total current assets	96,713,000		124,849,000		96,713,000		124,849,000		108,872,000
Other noncurrent assets	6,919,000		11,012,000		6,919,000		11,012,000		8,671,000
Total assets	103,632,000	[2]	135,861,000	[2]	103,632,000	[2]	135,861,000	[2]	117,543,000	[2]
Accounts payable	31,135,000		37,229,000		31,135,000		37,229,000		38,193,000
Billings in excess of costs and estimated earnings	17,979,000	[1]	41,386,000	[1]	17,979,000	[1]	41,386,000	[1]	22,251,000	[1]
Accrued expenses and other current liabilities	3,027,000		9,147,000		3,027,000		9,147,000		5,129,000
Total current liabilities	52,141,000		87,762,000		52,141,000		87,762,000		65,573,000
Noncurrent liabilities	0		0		0		0		4,000
Total liabilities	52,141,000	[2]	87,762,000	[2]	52,141,000	[2]	87,762,000	[2]	65,577,000	[2]
Number of Active Joint Venture Projects	2				2
Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Number of Active Joint Venture Projects	9				9
Reporting Entitys Interest in Joint Venture [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	700,000,000				700,000,000
Other Partners Interest in Partnerships [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	1,200,000,000				1,200,000,000
Minimum [Member] | Joint Venture Consolidated [Member] | Consolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	246,000,000				246,000,000
Proportionate Share of the Consolidated Joint Ventures Equity Owned by or Beneficial Interest in the Reporting Entity Directly or Indirectly	45.00%				45.00%
Construction	55,000,000		54,500,000		96,600,000		97,200,000
Net Cash Provided by (Used in) Operating Activities					(1,900,000)		16,800,000
Minimum [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	57,800,000				57,800,000
Proportionate Share of the Consolidated Joint Ventures Equity Owned by or Beneficial Interest in the Reporting Entity Directly or Indirectly	20.00%				20.00%
Minimum [Member] | Joint Venture Unconsolidated [Member] | Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	54,100,000				54,100,000
Minimum [Member] | Reporting Entitys Interest in Joint Venture [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	500,000				500,000
Minimum [Member] | Reporting Entitys Interest in Joint Venture [Member] | Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	21,500,000				21,500,000
Maximum [Member] | Joint Venture Consolidated [Member] | Consolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	319,300,000				319,300,000
Proportionate Share of the Consolidated Joint Ventures Equity Owned by or Beneficial Interest in the Reporting Entity Directly or Indirectly	60.00%				60.00%
Maximum [Member] | Joint Venture Unconsolidated [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	1,200,000,000				1,200,000,000
Proportionate Share of the Consolidated Joint Ventures Equity Owned by or Beneficial Interest in the Reporting Entity Directly or Indirectly	50.00%				50.00%
Maximum [Member] | Joint Venture Unconsolidated [Member] | Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	130,000,000				130,000,000
Maximum [Member] | Reporting Entitys Interest in Joint Venture [Member] | Unconsolidated Construction Joint Venture [Member]
Construction Joint Venture [Line Items]
Revenue Remaining to be Recognized on Unconsolidated Construction Joint Ventures	212,000,000				212,000,000
Maximum [Member] | Reporting Entitys Interest in Joint Venture [Member] | Line Item Joint Venture [Member]
Construction Joint Venture [Line Items]
Construction Contract Value	$ 54,900,000				$ 54,900,000

[1] The volume and stage of completion of contracts from our consolidated construction joint ventures may cause fluctuations in cash and cash equivalents, as well as billings in excess of costs and estimated earnings between periods.

[2] The assets and liabilities of each joint venture relate solely to that joint venture. The decision to distribute joint venture cash and cash equivalents and assets must generally be made jointly by all of the partners and, accordingly, these cash and cash equivalents and assets generally are not available for the working capital needs of Granite.