Accumulated Other Comprehensive Income (Loss) - Rollforward of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands		9 Months Ended
Jan. 01, 2018	Sep. 30, 2018
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Amounts reclassified from accumulated other comprehensive income (loss)		$ (184)
Amounts reclassified to accumulated other comprehensive income (loss) from retained earnings due to the stranded tax effects of the 2017 Tax Cuts and Jobs Act	$ 286	286
Change in accumulated other comprehensive income (loss)		102
AOCI Including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance as of December 31, 2017	$ 380	380
Balance as of September 30, 2018		$ 482

Tax Cuts And Jobs Act, Reclassification From AOCI To Retained Earnings, Tax Effect

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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- Definition

Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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