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Accounting Policies - New Accounting Standards (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
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Sep. 30, 2017 | Sep. 30, 2017 | Sep. 30, 2016
Accounting Policies [Abstract] |  |  |
Proceeds and Excess Tax Benefit from Share-based Compensation | $ 300 | $ 1,200 |
Excess Tax Benefits from Share-Based Compensation | $ 300 | 1,170 | $ 0
Payments Related to Tax Withholding for Share-based Compensation |  | $ 2,283 | $ 1,975

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- Definition Excess Tax Benefits from Share-Based Compensation + References No definition available. + Details
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- Definition Amount of cash outflow to satisfy an employee's income tax withholding obligation as part of a net-share settlement of a share-based award. + References Reference 1: 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 aggregate cash inflow comprised of the amount received from (a) employees to acquire the entity's shares under incentive awards, including stock option exercises and restricted stock arrangements, and (b) the excess tax benefit arising from such transactions. + References No definition available. + Details
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