Equity (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014		Dec. 31, 2012
Stockholders' Equity [Roll Forward]
Stockholders' equity, beginning balance	$ 817,106				$ 786,344
Purchase of common stock	(3,191)	[1]	(4,278)	[2]
Other transactions with shareholders	2,767	[3]	4,745	[3]
Transactions with noncontrolling interests, net	(260)		4,264
Net Loss Attributable to Parent	(8,560)		(20,553)
Comprehensive income (loss):
Net loss	(8,610)		(21,261)
Dividends on common stock	(5,115)		(5,083)
Stockholders' equity, ending balance	802,697		764,731		786,344
Shares Purchased for Tax Withholding for Share Based Compensation	98,000		110,000
Granite Construction [Member]
Stockholders' Equity [Roll Forward]
Stockholders' equity, beginning balance	794,385				781,940
Purchase of common stock	(3,191)	[1]	(4,278)	[2]
Other transactions with shareholders	2,767	[3]	4,745	[3]
Transactions with noncontrolling interests, net	0		0
Net Loss Attributable to Parent	(8,560)
Comprehensive income (loss):
Net loss			(20,553)
Dividends on common stock	(5,115)		(5,083)
Stockholders' equity, ending balance	780,286		756,771		781,940
Noncontrolling Interest [Member]
Stockholders' Equity [Roll Forward]
Stockholders' equity, beginning balance	22,721				4,404
Purchase of common stock	0	[1]	0	[2]
Other transactions with shareholders	0	[3]	0	[3]
Transactions with noncontrolling interests, net	(260)		4,264
Comprehensive income (loss):
Net loss	(50)		(708)
Dividends on common stock	0		0
Stockholders' equity, ending balance	$ 22,411		$ 7,960		$ 4,404

[1] Represents 98,000 shares purchased in connection with employee tax withholding for shares/units vested under our Amended and Restated 1999 Equity Incentive Plan.

[2] Represents 110,000 shares purchased in connection with employee tax withholding for shares/units vested under our Amended and Restated 1999 Equity Incentive Plan.

[3] Amounts are comprised primarily of amortized restricted stock and units.