17. Equity

The following tables summarize our equity activity for the periods presented (in thousands):

	Granite Construction Incorporated			Non-controlling Interests			Total Equity
Balance at December 31, 2017	$	945,108		$	47,697		$	992,805
Net income		35,864			7,490			43,354
Purchases of common stock¹		(6,369	)		—			(6,369	)
Dividends on common stock		(17,242	)		—			(17,242	)
Effect of adopting Topic 606		(15,202	)		—			(15,202	)
Issuance of common stock for Layne acquisition²		321,075			—			321,075
Issuance of common stock for 8.0% Convertible Notes³		53,098			—			53,098
Premium on 8.0% Convertible Notes⁴		30,702			—			30,702
Transactions with non-controlling interests		—			(10,080	)		(10,080	)
Other transactions with shareholders and employees⁵		14,258			—			14,258
Balance at September 30, 2018	$	1,361,292		$	45,107		$	1,406,399


Balance at December 31, 2016	$	885,988		$	36,603		$	922,591
Net income		36,325			4,151			40,476
Purchases of common stock⁶		(6,713	)		—			(6,713	)
Dividends on common stock		(15,532	)		—			(15,532	)
Transactions with non-controlling interests		—			(3,502	)		(3,502	)
Other transactions with shareholders and employees⁵		14,488			—			14,488
Balance at September 30, 2017	$	914,556		$	37,252		$	951,808

¹Represents 108,000 shares purchased in connection with employee tax withholding for restricted stock units vested under our 2012 Equity Incentive Plan.

²Represents 5,624,000 shares issued in connection with the Layne acquisition wherein each share of Layne common stock was exchanged for 0.27 shares of Granite common stock. See Note 3 for further information.

³Represents approximately 1,200,000 shares issued in connection with the conversion of the 8.0% Convertible Notes. See Note 14 for further discussion.

⁴Represents premium associated with the conversion feature on the 8.0% Convertible Notes assumed from the acquisition of Layne. See Note 14 for further discussion.

⁵Amounts are comprised primarily of amortized restricted stock units.

⁶Represents 136,000 shares purchased in connection with employee tax withholding for restricted stock units vested under our 2012 Equity Incentive Plan.