Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current Assets
Cash and cash equivalents	$ 86,433	$ 79,895
Short-term investments	16,129	43,188
Accounts receivable, less allowance for doubtful accounts of $— at December 31, 2017 and 2016	144,150	92,346
Other receivables	26,578	15,897
Inventory, net	122,542	105,117
Prepaid expenses and other current assets	17,282	16,459
Total Current Assets	413,114	352,902
Property, plant and equipment, net	85,079	84,469
Deferred tax assets, net	23,428	38,036
Goodwill	3,492	3,492
Other assets	13,725	12,234
Long-term investments	130,256	176,102
Total Assets	669,094	667,235
Current Liabilities
Accounts payable	60,632	77,342
Unearned revenue	13,070	16,326
Accrued expenses	13,232	12,434
Accrued wages and benefits	15,948	20,433
Income tax payable	3,936
Total Current Liabilities	106,818	126,535
Non-current unearned revenue	4,556	6,333
Other non-current liabilities	34,209	28,050
Bonds payable	25,600	26,800
Total Liabilities	171,183	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 48,485 shares outstanding at December 31, 2017 and 79,652 shares issued and 48,472 shares outstanding at December 31, 2016	797	797
Additional paid-in capital	260,515	252,957
Accumulated other comprehensive loss	(3,295)	(12,188)
Retained earnings	922,178	921,942
Less treasury stock at cost: 31,167 and 31,180 shares at December 31, 2017 and 2016, respectively	(682,284)	(683,991)
Total Stockholders' Equity	497,911	479,517
Total Liabilities and Stockholders' Equity	$ 669,094	$ 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.