Stockholders' Investment

3 Months Ended

Mar. 31, 2013

Equity [Abstract]

Stockholders' investment

6. Stockholders’ Investment

Changes in stockholders’ investment consisted of the following (in thousands):

	Three Months Ended March 31,
	2013		2012
Beginning balance	$	392,079	$	295,953
Net income	10,582		7,931
Other changes	9,566		1,160
Ending balance	$	412,227	$	305,044

In January 2013, the underwriters for the Company's public offering of common stock exercised in full their over-allotment option to purchase an additional 525,000 shares of common stock at a price of $17.25 per share to the public. The sale of the additional shares resulted in additional net proceeds to the Company of approximately $8.5 million after deducting the underwriting discount and estimated expenses.