Stock-Based Compensation Plans (Tables)

12 Months Ended

Dec. 31, 2012

Stock-Based Compensation Plans

Schedule of share-based compensation expenses

	AWR						GSWC
	For The Years Ended December 31,						For The Years Ended December 31,
(in thousands)	2012		2011		2010		2012		2011		2010
Stock-based compensation related to:
Stock options granted to employees and directors	$	150	$	302	$	579	$	147	$	307	$	438
Restricted stock units granted to employees	1,402		927		645		1,141		747		443
Restricted stock units granted to directors	379		291		258		379		291		258
Total stock-based compensation expense	$	1,931	$	1,520	$	1,482	$	1,667	$	1,345	$	1,139

Schedule of assumptions used to estimate fair value of each option grant on the grant date using the Black-Scholes option-pricing model

	2011			2010
Weighted-average fair value of option granted	$	7.15		$	7.02
Risk-free interest rate	2.48		%	2.48		%
Expected annual dividend yield	3.04		%	3.04		%
Expected volatility factor	28.98		%	28.98		%
Expected option term (in years)	5			5

Summary of stock option activity

	Number of Options		Weighted Average Exercise Price			Weighted Average Remaining Contractual Term	Aggregate Intrinsic Value
Options outstanding at January 1, 2012	619,984		$	32.75
Granted	—		—
Exercised	(409,700	)	(32.45		)
Forfeited or expired	(8,705	)	(31.38		)
Options outstanding at December 31, 2012	201,579		$	33.43		0.71	$	2,932,672
Options exercisable at December 31, 2012	184,755		$	33.44		4.47	$	2,687,254

Summary of the status of Registrant's outstanding restricted stock units to employees and directors

	Number of Restricted Share Units		Weighted Average Grant-Date Value
Restricted share units at January 1, 2012	137,673		$	34.37
Granted	64,943		36.97
Vested	(52,044	)	(32.50		)
Forfeited	(906	)	(35.52		)
Restricted share units at December 31, 2012	149,666		$	34.05