Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net income	$ 121,887	$ 129,437	$ 143,086
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	83,003	71,564	72,397
Impairment of fixed assets	48,551	0	0
Equity method earnings	(456)	(1,048)	0
Gain on step acquisition	(13,644)	0	0
Loss on extinguishment of debt	7,220	0	0
Japan customs expense	0	0	31,355
Foreign currency (gains)/losses	16,381	(3,014)	8,863
Stock-based compensation	26,609	19,314	8,890
Deferred taxes	(14,929)	39,213	(17,652)
Changes in operating assets and liabilities:
Accounts receivable	(10,453)	(103)	3,357
Inventories, net	(33,371)	7,537	9,801
Prepaid expenses and other	(1,536)	14,250	37,789
Other assets	887	(11,658)	(3,969)
Accounts payable	(9,164)	6,834	13,443
Accrued expenses	(7,433)	22,490	(33,624)
Other liabilities	(10,814)	7,739	1,527
Net cash provided by (used in) operating activities	202,738	302,555	275,263
Cash flows from investing activities:
Purchases of property and equipment	(70,371)	(60,156)	(50,221)
Proceeds on investment sales	11,536	11,269	18,132
Purchases of investments	(11,420)	(11,332)	(17,080)
Acquisitions and investments in equity investees	(38,506)	(31,745)	(8,692)
Net cash used in investing activities	(108,761)	(91,964)	(57,861)
Cash flows from financing activities:
Payment of cash dividends	(80,581)	(76,058)	(78,438)
Repurchase of shares of common stock	(69,565)	(71,731)	(247,208)
Exercise of employee stock options and taxes paid related to the net shares settlement of stock awards	10,777	24,443	14,307
Income tax benefit of equity awards	0	0	5,651
Payments on long-term debt	(552,500)	(103,226)	(56,151)
Payment of debt issuance costs	(7,243)	0	(6,596)
Proceeds from long-term debt	582,398	67,000	233,721
Net cash used in financing activities	(116,714)	(159,572)	(134,714)
Effect of exchange rate changes on cash	(16,751)	18,134	(14,796)
Net increase (decrease) in cash and cash equivalents	(39,488)	69,153	67,892
Cash and cash equivalents, beginning of period	426,399	357,246	289,354
Cash and cash equivalents, end of period	$ 386,911	$ 426,399	$ 357,246