Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Current Assets
Cash and cash equivalents	$ 128,253	$ 79,895
Short-term investments	31,385	43,188
Accounts receivable, less allowance for doubtful accounts of $— at September 30, 2017 and December 31, 2016	101,613	92,346
Other receivables	18,541	15,137
Income tax receivable, net		760
Inventory, net	116,230	105,117
Prepaid expenses and other current assets	23,127	16,459
Total Current Assets	419,149	352,902
Property, plant and equipment, net	85,665	84,469
Deferred tax assets, net	37,130	38,036
Goodwill	3,492	3,492
Other assets	13,135	12,234
Long-term investments	136,987	176,102
Total Assets	695,558	667,235
Current Liabilities
Accounts payable	73,127	77,342
Unearned revenue	13,651	16,326
Accrued expenses	15,099	12,434
Accrued wages and benefits	15,345	20,433
Income tax payable, net	7,696
Total Current Liabilities	124,918	126,535
Non-current unearned revenue	4,918	6,333
Other non-current liabilities	34,756	28,050
Bonds payable	26,800	26,800
Total Liabilities	191,392	187,718
Commitments and contingencies (see Note 14)
Stockholders’ Equity
Common stock, par value $0.01 per share; 200,000 shares authorized; 79,652 shares issued and 48,003 shares outstanding at September 30, 2017 and 79,652 shares issued and 48,472 shares outstanding at December 31, 2016	797	797
Additional paid-in capital	258,655	252,957
Accumulated other comprehensive loss	(4,256)	(12,188)
Retained earnings	941,845	921,942
Less treasury stock at cost: 31,649 and 31,180 shares at September 30, 2017 and December 31, 2016, respectively	(692,875)	(683,991)
Total Stockholders’ Equity	504,166	479,517
Total Liabilities and Stockholders’ Equity	$ 695,558	$ 667,235

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.