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Difference Between Provision For Income Taxes And U.S. Federal Statutory Rate (Detail) | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Income Taxes |  |  |
Provision at U.S. federal statutory rate | 35.00% | 35.00% | 35.00%
State taxes, net of federal benefit | 1.90% | 2.80% | 2.60%
U.S. manufacturing credit | (1.40%) | (1.50%) | (1.30%)
Research tax credits | (0.30%) | (0.30%) | (0.30%)
Excess tax benefit on stock compensation | (2.20%) | (1.10%) |
Other | 0.80% | 0.40% | 0.30%
Effective Income Tax Rate Continuing Operations Excluding Change in Tax Rate, Total | 27.40% | 29.40% | 29.70%
U.S. Tax Cuts & Jobs Act (U.S. Tax Reform) | 15.70% |  |
Effective Income Tax Rate Reconciliation, Percent, Total | 43.10% | 29.40% | 29.70%
State Administration of Taxation, China |  |  |
Income Taxes |  |  |
International income tax rate differential | (6.50%) | (6.20%) | (6.80%)
Other |  |  |
Income Taxes |  |  |
International income tax rate differential | 0.10% | 0.30% | 0.20%

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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)(2)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 + Details
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