Earnings Per Share (Tables)

3 Months Ended

Mar. 31, 2013

Earnings Per Share [Abstract]

Summary of reconciliation of the numerators and denominators used in the basic and diluted per share computations

	Three Months Ended March 31,
	2013				2012
	Class A		Class B		Class A		Class B
	(in thousands, except per share data)
Basic and diluted net income per share:
Numerator:
Allocation of net income	$	5,170	$	1,305	$	6,390	$	1,620
Denominator:
Weighted-average shares outstanding		20,066,755		5,576,775		19,996,285		5,576,775
Basic net income per share	$	0.26	$	0.23	$	0.32	$	0.29
Diluted net income per share:
Numerator:
Allocation of net income	$	5,170	$	1,305	$	6,390	$	1,620
Denominator:
Number of shares used in basic computation		20,066,755		5,576,775		19,996,285		5,576,775
Weighted-average shares effect of dilutive securities
Add: Director and employee stock options		291,477		—		364,836		—
Number of shares used in per share computations		20,358,232		5,576,775		20,361,121		5,576,775
Diluted net income per share	$	0.25	$	0.23	$	0.31	$	0.29

Reconciliation of diluted shares outstanding

	Three Month Ended March 31,
	2013		2012
Number of Class A shares excluded		1,212,000		1,235,000