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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables) | 12 Months Ended
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Dec. 31, 2017
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES |
Schedule of changes in accumulated other comprehensive income (loss), by component | Changes in accumulated other comprehensive income (loss), by component, were as follows (in thousands):
|  |  | Projected |  |  |  |  |  |  |  |  |  |
|  |  | Pension |  |  |  |  |  |  |  |  |  |
|  |  | Benefit |  | Translation |  | Short Term |  |  |  |
|  |  | Obligation |  | Adjustment |  | Investment |  | Total |
Balance at December 31, 2014 |  |  | $ | (2,672) |  | $ | (249) |  | $ | — |  | $ | (2,921) |
Adjust funded status of pension plan, net of tax of $0.7 million |  |  |  | (809) |  |  | — |  |  | — |  |  | (809) |
Foreign currency translation adjustment |  |  |  | — |  |  | 26 |  |  | — |  |  | 26 |
Balance at December 31, 2015 |  |  |  | (3,481) |  |  | (223) |  |  | — |  |  | (3,704) |
Adjust funded status of pension plan, net of tax of $0.7 million |  |  |  | 5,251 |  |  | — |  |  | — |  |  | 5,251 |
Foreign currency translation adjustment |  |  |  | — |  |  | (687) |  |  | — |  |  | (687) |
Unrealized gain on marketable securities |  |  |  | — |  |  | — |  |  | 868 |  |  | 868 |
Balance at December 31, 2016 |  |  |  | 1,770 |  |  | (910) |  |  | 868 |  |  | 1,728 |
Adjust funded status of pension plan, net of tax of $0.7 million |  |  |  | 1,357 |  |  | — |  |  | — |  |  | 1,357 |
Foreign currency translation adjustment |  |  |  | — |  |  | 1,265 |  |  | — |  |  | 1,265 |
Reclassifications of gains on sale of marketable securities to net income |  |  |  | — |  |  | — |  |  | (1,044) |  |  | (1,044) |
Unrealized gain on marketable securities |  |  |  | — |  |  | — |  |  | 440 |  |  | 440 |
Balance at December 31, 2017 |  |  | $ | 3,127 |  | $ | 355 |  | $ | 264 |  | $ | 3,746 |
Schedule of reclassification from accumulated other comprehensive income | Amounts reclassified from accumulated other comprehensive income to net income were as follows (in thousands):
|  |  |  | 2017 |  |  | 2016 |  |  | 2015
Pension and other postretirement benefit plans |  |  | $ | 716 |  | $ | 1,300 |  | $ | 200
Realized gains on marketable securities |  |  |  | (1,044) |  |  | — |  |  | —
Total |  |  | $ | (328) |  | $ | 1,300 |  | $ | 200
Schedule of percentage of revenues generated from a single customer that exceeds 10% of the Company's consolidated revenue |
Customer |  | 2017 |  | 2016 |  | 2015 |
Verizon |  | 10 | % | 12 | % | 19 | %
AT&T |  | 13 | % | 14 | % | 17 | %
Schedule of percentage of accounts receivable, from customers that exceed 10% of the Company's consolidated accounts receivable, net of allowances |
Customer |  | 2017 |  | 2016 |
AT&T |  | 18 | % | 17 | %
Verizon |  | — | % | 12 | %
Schedule of assets and liabilities of the Company measured at fair value on a recurring basis |
|  |  |  |  | December 31, 2017 |  |  |  |
|  |  |  |  | Significant Other |  |  |  |
|  | Quoted Prices in |  | Observable |  |  |  |
|  | Active Markets |  | Inputs |  |  |  |
Description |  | (Level 1) |  | (Level 2) |  | Total |
Certificates of deposit |  | $ | — |  | $ | 391 |  | $ | 391 |
Money market funds |  |  | 2,894 |  |  | — |  |  | 2,894 |
Short term investments |  |  | 555 |  |  | 6,521 |  |  | 7,076 |
Commercial paper |  |  | — |  |  | 49,954 |  |  | 49,954 |
Interest rate swap |  |  | — |  |  | 52 |  |  | 52 |
Total assets and liabilities measured at fair value |  | $ | 3,449 |  | $ | 56,918 |  | $ | 60,367 |
|  | December 31, 2016 |
|  |  |  |  | Significant Other |  |  |  |
|  | Quoted Prices in |  | Observable |  |  |  |
|  | Active Markets |  | Inputs |  |  |  |
Description |  | (Level 1) |  | (Level 2) |  | Total |
Certificates of deposit |  | $ | — |  | $ | 391 |  | $ | 391 |
Money market funds |  |  | 29,027 |  |  | — |  |  | 29,027 |
Short term investments |  |  | 1,751 |  |  | 7,486 |  |  | 9,237 |
Commercial paper |  |  | — |  |  | 29,981 |  |  | 29,981 |
Total assets measured at fair value |  | $ | 30,778 |  | $ | 37,858 |  | $ | 68,636 |
Schedule of reconciliation from basic to diluted weighted average common shares outstanding | The reconciliation from basic to diluted weighted average shares of Common Stock outstanding is as follows (in thousands):
|  | Year ended December 31, |
|  | 2017 |  | 2016 |  | 2015 |
Basic weighted-average shares of common stock outstanding |  | 16,138 |  | 16,131 |  | 16,022 |
Stock options |  | 72 |  | 96 |  | 120 |
Diluted weighted-average shares of common stock outstanding |  | 16,210 |  | 16,227 |  | 16,142 |
Schedule of anti-dilutive potential shares that were excluded from the computation of diluted weighted average shares outstanding | The following notes the number of potential shares of common stock not included in the above calculation because the effects of such were anti‑dilutive (in thousands of shares):
|  | For the Year Ended |
|  | December 31, |
|  | 2017 |  | 2016 |  | 2015 |
Stock options |  | 7 |  | 5 |  | 2 |
Total |  | 7 |  | 5 |  | 2 |

X
- Definition Tabular disclosure of the percentage that a specified receivable or amount at risk from a counterparty under a contractual arrangement is to a specified benchmark, such as total receivables, net revenues, pretax results. Risk is the materially adverse effects of loss attributable to (a) the failure to collect a significant receivable from a major customer or group of homogeneous accounts, or (b) a failure by a counterparty to perform under terms of a contractual arrangement. + References No definition available. + Details
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- Definition Tabular disclosure of the percentage that revenues in the period from one or more significant customers is to net revenues, as defined by the entity, such as total net revenues, product line revenues, segment revenues. The risk is the materially adverse effects of loss of a significant customer. + References No definition available. + Details
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- Definition Tabular disclosure of the components of accumulated other comprehensive income (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580 + Details
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- Definition Tabular disclosure of securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) in the future that were not included in the computation of diluted EPS because to do so would increase EPS amounts or decrease loss per share amounts for the period presented, by antidilutive securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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- Definition Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19190-110258 + Details
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