Earnings per Share (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Numerator:
Income from continuing operations	$ 5,847,000	$ 6,619,000	$ 10,263,000	$ 13,164,000
Income (loss) from discontinued operations	401,000	(899,000)	429,000	(1,477,000)
Net income	$ 6,248,000	$ 5,720,000	$ 10,692,000	$ 11,687,000
Denominator:
Weighted average shares of common stock outstanding	12,069,150	13,050,346	12,085,221	13,111,348
Effect of dilutive common stock equivalents	90,136	99,068	90,764	88,859
Weighted average shares of common stock outstanding	12,159,286	13,149,414	12,175,985	13,200,207
Basic earnings per share
Earnings per share from continuing operations	$ 0.48	$ 0.50	$ 0.85	$ 0.99
Earnings (loss) per share from discontinued operations	0.03	(0.06)	0.03	(0.10)
Earnings per share	0.51	0.44	0.88	0.89
Diluted earnings per share
Earnings per share from continuing operations	0.48	0.50	0.84	1.00
Earnings (loss) per share from discontinued operations	0.03	(0.06)	0.04	(0.11)
Earnings per share	$ 0.51	$ 0.44	$ 0.88	$ 0.89