Equity Plans (Tables)

12 Months Ended

Dec. 31, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan

A summary of compensation costs charged to income, proceeds from the exercise of stock options and similar instruments and the tax benefit realized from stock options and similar instruments exercised, that are recorded to additional paid-in capital and common stock, by award type, are presented below for the years ended December 31:

	2015		2014	2013
Compensation costs charged to income:
ESPP	$	158	148	128
Restricted stock and deferred restricted stock	1,445		883	784
Total compensation costs charged to income	$	1,603	1,031	912
Proceeds from the exercise of stock options and similar instruments:
Stock options	$	—	1,044	198
ESPP	895		839	722
DRSPP	—		34	84
Total proceeds from the exercise of stock options and similar instruments	$	895	1,917	1,004
Excess tax benefits realized from share options exercised and stock issuance:
Stock options	$	—	213	(69	)
Restricted stock and deferred restricted stock	634		249	97
Total excess tax benefits realized from share options exercised and stock issuance	$	634	462	28

Schedule of Share-based Compensation, Stock Options, Activity

As of December 31, 2015, there are no outstanding options and no option award activity during the year ended December 31, 2015.

Schedule of Share-based Compensation, Restricted Stock Units Award Activity

A summary of SJW Corp.'s restricted and deferred restricted stock awards as of December 31, 2015, and changes during the year ended December 31, 2015, are presented below:

	Units		Weighted- Average Grant- Date Fair Value
Outstanding as of January 1, 2015	259,807		$	18.56
Issued	32,516		$	30.98
Vested	(83,086	)	$	32.79
Forfeited or expired	—		$	—
Outstanding as of December 31, 2015	209,237		$	21.49
Shares vested as of December 31, 2015	115,693		$	16.52

Schedule of Nonvested Restricted Stock Units Activity

A summary of the status of SJW Corp.'s nonvested restricted and deferred restricted stock awards as of December 31, 2015, and changes during the year ended December 31, 2015, are presented below:

	Units		Weighted-  Average Grant- Date Fair Value
Nonvested as of January 1, 2015	130,467		$	20.75
Granted	32,516		$	30.98
Vested	(69,439	)	$	16.28
Forfeited	—		$	—
Nonvested as of December 31, 2015	93,544		$	27.63