Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 716,522	$ 642,319
Investments	1,835,351	2,751,382
Accounts receivable, net	502,968	533,825
Inventories	299,614	270,294
Other current assets	84,123	72,314
Total current assets	3,438,578	4,270,134
Property, plant and equipment, net	349,319	349,278
Intangible assets, net	231,733	228,395
Goodwill	362,331	359,819
Other assets	107,496	116,728
Total assets	4,489,457	5,324,354
Current liabilities:
Notes payable and debt	354	100,273
Accounts payable	70,645	64,537
Accrued employee compensation	31,791	69,024
Deferred revenue and customer advances	214,979	166,840
Accrued income taxes	100,259	73,008
Accrued warranty	12,626	13,026
Other current liabilities	103,694	119,449
Total current liabilities	534,348	606,157
Long-term liabilities:
Long-term debt	1,247,630	1,897,501
Long-term portion of retirement benefits	67,533	67,334
Long-term income tax liabilities	457,087	456,949
Other long-term liabilities	67,965	62,625
Total long-term liabilities	1,840,215	2,484,409
Total liabilities	2,374,563	3,090,566
Commitments and contingencies (Notes 6, 7 and 11)
Stockholders' equity:
Preferred stock, par value $0.01 per share, 5,000 shares authorized, none issued at March 31, 2018 and December 31, 2017
Common stock, par value $0.01 per share, 400,000 shares authorized, 160,200 and 159,845 shares issued, 78,319 and 79,337 shares outstanding at March 31, 2018 and December 31, 2017, respectively	1,602	1,598
Additional paid-in capital	1,779,142	1,745,088
Retained earnings	5,513,362	5,405,380
Treasury stock, at cost, 81,881 and 80,509 shares at March 31, 2018 and December 31, 2017, respectively	(5,090,581)	(4,808,211)
Accumulated other comprehensive loss	(88,631)	(110,067)
Total stockholders' equity	2,114,894	2,233,788
Total liabilities and stockholders' equity	$ 4,489,457	$ 5,324,354

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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Balance Type:	credit
Period Type:	instant

- 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.