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Stockholders' Equity (Narratives) (Details) - USD ($) | Dec. 31, 2018 | Nov. 08, 2018 | Nov. 02, 2018
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Class Of Stock [Line Items] |  |  |
Stock repurchase, authorized amount |  |  | $ 60,000,000
Maximum amount of common stock may be repurchased in calendar year | $ 35,000,000 |  |
2014 Employee Stock Purchase Plan |  |  |
Class Of Stock [Line Items] |  |  |
Authorized shares for issuance |  | 7,500,000 |

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- Definition The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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