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The Company and Its Accounting Policies - Reconciliation of Numerators and Denominators of Basic and Diluted (Loss) Income Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2018 | Mar. 31, 2017 | Mar. 31, 2016
Numerator: |  |  |  |  |  |  |  |  |  |  |
Net (loss) income | $ 833 | $ (11,622) | $ 10 | $ 935 | $ 1,801 | $ 1,840 | $ 1,297 | $ 85 | $ (9,844) | $ 5,023 | $ 6,131
Denominator: |  |  |  |  |  |  |  |  |  |  |
Weighted average common shares and SEUs outstanding |  |  |  |  |  |  |  |  | 9,764 | 9,716 | 9,976
Basic (loss) income per share | $ 0.09 | $ (1.19) |  | $ 0.10 | $ 0.18 | $ 0.19 | $ 0.13 | $ 0.01 | $ (1.01) | $ 0.52 | $ 0.61
Numerator: |  |  |  |  |  |  |  |  |  |  |
Net (loss) income | $ 833 | $ (11,622) | $ 10 | $ 935 | $ 1,801 | $ 1,840 | $ 1,297 | $ 85 | $ (9,844) | $ 5,023 | $ 6,131
Denominator: |  |  |  |  |  |  |  |  |  |  |
Weighted average common shares and SEUs outstanding |  |  |  |  |  |  |  |  | 9,764 | 9,716 | 9,976
Stock options outstanding |  |  |  |  |  |  |  |  |  | 12 | 7
Weighted average common and potential common shares outstanding |  |  |  |  |  |  |  |  | 9,764 | 9,728 | 9,983
Diluted (loss) income per share | $ 0.09 | $ (1.19) |  | $ 0.10 | $ 0.18 | $ 0.19 | $ 0.13 | $ 0.01 | $ (1.01) | $ 0.52 | $ 0.61

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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. + References Reference 1: 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 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 55 -Paragraph 52 -URI http://asc.fasb.org/extlink&oid=96948231&loc=d3e4984-109258 Reference 3: 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(19)) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=96947427&loc=d3e1252-109256 Reference 5: 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(21)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 6: 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(23)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
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