Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Current Assets
Cash and cash equivalents	$ 79,895	$ 84,550
Short-term investments	43,188	34,396
Accounts receivable, less allowance for doubtful accounts of $— and $19 at December 31, 2016 and 2015, respectively	92,346	71,917
Other receivables	15,137	19,321
Income tax receivable, net	760
Inventory, net	105,117	91,533
Prepaid expenses and other current assets	16,459	10,145
Total Current Assets	352,902	311,862
Property, plant and equipment, net	84,469	73,233
Deferred tax assets, net	38,036	37,015
Goodwill	3,492	3,492
Other assets	12,234	9,276
Long-term investments	176,102	198,026
Total Assets	667,235	632,904
Current Liabilities
Accounts payable	77,342	48,668
Unearned revenue	16,326	16,615
Accrued expenses	12,434	12,108
Accrued wages and benefits	20,433	12,857
Income tax payable, net		2,395
Total Current Liabilities	126,535	92,643
Non-current unearned revenue	6,333	7,965
Other non-current liabilities	28,050	24,236
Bonds payable	26,800	27,900
Total Liabilities	187,718	152,744
Commitments and contingencies (see Note 13)
Stockholders' Equity
Common stock, par value $0.01 per share; 200,000 shares authorized; 79,652 shares issued and 48,472 shares outstanding at December 31, 2016 and 79,652 shares issued and 49,558 shares outstanding at December 31, 2015	797	797
Additional paid-in capital	252,957	246,879
Accumulated other comprehensive loss	(12,188)	(8,969)
Retained earnings	921,942	906,772
Less treasury stock at cost: 31,180 and 30,094 shares at December 31, 2016 and 2015, respectively	(683,991)	(665,319)
Total Stockholders' Equity	479,517	480,160
Total Liabilities and Stockholders' Equity	$ 667,235	$ 632,904

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.