Equity Incentive Plan (Tables)

12 Months Ended

Dec. 31, 2013

Equity Incentive Plan

Schedule of stock option activity

	Number of Shares Subject to Option			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term	Aggregate Intrinsic Value
Options outstanding, December 31, 2010		587,555			16.00	9.7 years	$—
Granted		543,380			15.27
Forfeited		(122,848	)		15.80
Expired		(8,074	)		16.00
Exercised		(1,962	)		16.00		Less than $0.1 million
Options outstanding, December 31, 2011		998,051		$	15.63	8.9 years	$2.2 million
Granted		236,893			23.87
Forfeited		(119,723	)		16.62
Expired		(156	)		16.00
Exercised		(97,870	)		16.04		$0.8 million
Options outstanding, December 31, 2012		1,017,195			17.25	8.2 years	$10.6 million
Granted		209,268			32.50
Forfeited		(37,232	)		23.00
Expired		(535	)		34.82
Exercised		(54,781	)		16.86		$1.0 million
Options outstanding, December 31, 2013		1,133,915			19.89	7.6 years	$14.0 million
Exercisable at December 31,
2011		130,942		$	16.00	8.7 years	$0.2 million
2012		287,036		$	15.74	7.9 years	$3.4 million
2013		498,176		$	16.51	7.1 years	$7.8 million

Schedule of unvested shares subject to option

	Number of Shares Subject to Option			Weighted Average Fair Value at Grant Date
Unvested balance, December 31, 2010		587,555			4.95
Granted		543,380			4.89
Forfeited		(122,848	)		4.93
Vested		(140,978	)		4.92
Unvested balance, December 31, 2011		867,109		$	4.92
Granted		236,893			7.76
Forfeited		(119,723	)		5.24
Vested		(254,120	)		4.96
Unvested balance, December 31, 2012		730,159		$	5.70
Granted		209,268			10.01
Forfeited		(37,232	)		7.21
Vested		(266,456	)		5.54
Unvested balance, December 31, 2013		635,739		$	7.10

Summary of assumptions used to value the stock options granted

	2013			2012			2011
Expected term (in years)		6.25			6.25			6.25
Expected volatility		43.86	%		44.08	%		43.07	%
Expected annual dividend		3.33	%		3.00	%		3.41	%
Risk-free rate		1.26	%		1.56	%		2.76	%

Schedule of restricted awards

	Restricted Awards			Weighted Average Fair Value at Grant Date
Unvested balance, December 31, 2010		195,437			15.98
Granted		273,473			15.19
Forfeited		(51,213	)		15.81
Vested		(74,466	)		16.10
Unvested balance, December 31, 2011		343,231			15.35
Granted		412,780			24.59
Forfeited		(48,599	)		18.26
Vested		(108,717	)		15.46
Unvested balance, December 31, 2012		598,695		$	21.37
Granted		194,302			32.43
Forfeited		(58,199	)		28.44
Vested		(239,647	)		20.96
Unvested balance, December 31, 2013		495,151		$	25.08