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Consolidated Statements Of Cash Flows - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
CASH FLOWS FROM OPERATING ACTIVITIES |  |  |  |  |  |
Net income |  | $ 110,940 | $ 60,251 |  | $ 44,467 |
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |  |  |  |
Depreciation and amortization |  | 9,482 | 7,936 |  | 6,917 |
Amortization of intangible assets |  | 2,103 | 1,051 |  | 0 |
Gain from disposal of short-term investments |  | (2) | (3) |  | (4) |
Impairment of long-term investments |  | 13 |  |  |  |
Stock-based compensation |  | 17,364 | 10,418 |  | 10,347 |
Loss on disposal of property and equipment |  | 33 | 10 |  | 18 |
Deferred income taxes |  | (3,373) | 911 |  | 471 |
Changes in operating assets and liabilities: |  |  |  |  |  |
Short-term investments |  | (2,710) |  |  |  |
Notes and accounts receivable |  | (14,620) | (29,179) |  | 2,359 |
Inventories |  | (24,777) | (410) |  | (10,410) |
Prepaid expenses and other current assets |  | (1,313) | (664) |  | (678) |
Other assets |  | (5) | 136 |  | 67 |
Notes and accounts payable |  | 9,198 | 7,651 |  | (415) |
Accrued expenses and other current liabilities |  | 12,180 | 11,020 |  | 5,543 |
Income tax payable |  | 6,876 | (4,301) |  | 9,507 |
Other liabilities |  | 4,179 | 1,119 |  | 536 |
Net cash provided by operating activities |  | 125,568 | 65,946 |  | 68,725 |
CASH FLOWS FROM INVESTING ACTIVITIES |  |  |  |  |  |
Purchase of held-to-maturity financial assets |  |  | (4,000) |  |  |
Proceeds from sale of held-to-maturity financial assets |  | 4,000 |  |  |  |
Business acquisition-net of cash, cash equivalents, and restricted cash acquired |  |  | (30,286) |  |  |
Increase of prepaid expenses and other current assets |  |  | (508) |  |  |
Purchase of property and equipment |  | (12,220) | (23,664) |  | (11,596) |
Net cash used in investing activities |  | (8,220) | (58,458) |  | (11,596) |
CASH FLOWS FROM FINANCING ACTIVITIES |  |  |  |  |  |
Proceeds from issuance of ordinary shares upon exercise of employee stock options |  | 93 | 494 |  | 514 |
Proceeds from bank loan |  | 25,000 |  |  |  |
Dividends paid |  | (22,899) | (20,765) |  | (20,224) |
Net cash provided by (used in) financing activities |  | 2,194 | (20,271) |  | (19,710) |
NET INCREASE (DECREASE) IN CASH, CASH EQUIVALENTS, AND RESTRICTED CASH |  | 119,542 | (12,783) | [1] | 37,419 | [1]
EFFECT OF EXCHANGE RATE CHANGES |  | (521) | (953) |  | (1,111) |
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, BEGINNING OF YEAR | [1] | 202,156 | 215,892 |  | 179,584 |
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, END OF YEAR |  | 321,177 | 202,156 | [1] | 215,892 | [1]
SUPPLEMENTAL INFORMATION |  |  |  |  |  |
Interest paid |  | 105 | 6 |  | 71 |
Income taxes paid |  | $ 24,300 | 20,494 |  | $ 5,892 |
Cash paid for business acquisition, net of cash, cash equivalents, and restricted cash acquired |  |  | 30,286 |  |  |
Shannon Systems |  |  |  |  |  |
CASH FLOWS FROM INVESTING ACTIVITIES |  |  |  |  |  |
Business acquisition-net of cash, cash equivalents, and restricted cash acquired |  |  | (30,286) |  |  |
SUPPLEMENTAL INFORMATION |  |  |  |  |  |
Fair value of assets acquired, net of cash, cash equivalents, and restricted cash acquired |  |  | 43,661 |  |  |
Other long-term liabilities |  |  | (5,735) |  |  |
Issuance of stock |  |  | (7,640) |  |  |
Cash paid for business acquisition, net of cash, cash equivalents, and restricted cash acquired |  |  | $ 30,286 |  |  |
[1] | The restricted cash is only included in the amount of "as adjusted" item.

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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Net Income -URI http://asc.fasb.org/extlink&oid=51831255 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(22)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(18)) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Other Comprehensive Income -URI http://asc.fasb.org/extlink&oid=51831270 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(20)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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- Definition Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3291-108585 + Details
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- Definition The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 + Details
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- Definition Amount of cash outflow through purchase of long-term held-to-maturity securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26853-111562 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 + Details
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- Definition The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585 + Details
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- Definition The cash inflow from bank borrowing during the year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3255-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 + Details
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- Definition The cash inflow associated with the sale of securities that had been designated as held-to-maturity. Excludes proceeds from maturities, prepayments and calls by the issuer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26853-111562 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585 + Details
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- Definition The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3255-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 + Details
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