Equity (Details) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015		Jun. 30, 2014
Stockholders' Equity [Roll Forward]
Stockholders' equity, beginning balance				$ 817,106		$ 786,344
Purchase of common stock				(3,332)	[1]	(4,369)	[2]
Other transactions with shareholders	[3]			5,092		7,989
Transactions with noncontrolling interests, net				(1,282)		12,804
Net Loss Attributable to Parent		$ 9,613	$ 13,641	1,053		(6,913)
Comprehensive income (loss):
Net income		9,539	22,207	929		945
Dividends on common stock				(10,233)		(10,170)
Stockholders' equity, ending balance		808,280	793,543	$ 808,280		$ 793,543
Shares Purchased for Tax Withholding for Share Based Compensation				102,000		113,000
Granite Construction [Member]
Stockholders' Equity [Roll Forward]
Stockholders' equity, beginning balance				$ 794,385		$ 781,940
Purchase of common stock				(3,332)	[1]	(4,369)	[2]
Other transactions with shareholders	[3]			5,092		7,989
Transactions with noncontrolling interests, net				0		0
Net Loss Attributable to Parent				1,053
Comprehensive income (loss):
Net income						(6,913)
Dividends on common stock				(10,233)		(10,170)
Stockholders' equity, ending balance		786,965	768,477	786,965		768,477
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	[3]			0		0
Transactions with noncontrolling interests, net				(1,282)		12,804
Comprehensive income (loss):
Net income				(124)		7,858
Dividends on common stock				0		0
Stockholders' equity, ending balance		$ 21,315	$ 25,066	$ 21,315		$ 25,066

[1] Represents 102,000 shares purchased in connection with employee tax withholding for units vested under our Amended and Restated 1999 Equity Incentive Plan.

[2] Represents 113,000 shares purchased in connection with employee tax withholding for units vested under our Amended and Restated 1999 Equity Incentive Plan.

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