Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current Assets
Cash and cash equivalents	$ 88,798	$ 79,895
Short-term investments	47,331	43,188
Accounts receivable, less allowance for doubtful accounts of $— at June 30, 2017 and December 31, 2016	79,891	92,346
Other receivables	14,561	15,137
Income tax receivable, net		760
Inventory, net	113,995	105,117
Prepaid expenses and other current assets	23,556	16,459
Total Current Assets	368,132	352,902
Property, plant and equipment, net	84,122	84,469
Deferred tax assets, net	40,296	38,036
Goodwill	3,492	3,492
Other assets	13,305	12,234
Long-term investments	159,634	176,102
Total Assets	668,981	667,235
Current Liabilities
Accounts payable	66,161	77,342
Unearned revenue	15,449	16,326
Accrued expenses	13,433	12,434
Accrued wages and benefits	16,303	20,433
Income tax payable, net	9,594
Total Current Liabilities	120,940	126,535
Non-current unearned revenue	5,351	6,333
Other non-current liabilities	32,527	28,050
Bonds payable	26,800	26,800
Total Liabilities	185,618	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 47,747 shares outstanding at June 30, 2017 and 79,652 shares issued and 48,472 shares outstanding at December 31, 2016	797	797
Additional paid-in capital	256,821	252,957
Accumulated other comprehensive loss	(6,816)	(12,188)
Retained earnings	931,044	921,942
Less treasury stock at cost: 31,905 and 31,180 shares at June 30, 2017 and December 31, 2016, respectively	(698,483)	(683,991)
Total Stockholders’ Equity	483,363	479,517
Total Liabilities and Stockholders’ Equity	$ 668,981	$ 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.