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401(k) Plan (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan employer matching contribution percent	3.50%
Employer contributions	$ 500	$ 0	$ 0
Vesting period	3 years
Annual vesting percentage	33.00%
1% of participating employee contributions
Defined Benefit Plan Disclosure [Line Items]
Percentage of company matching to defined contribution plan	100.00%
Defined contribution plan employer matching contribution percent	1.00%
5% of participating employee contributions
Defined Benefit Plan Disclosure [Line Items]
Percentage of company matching to defined contribution plan	50.00%
Defined contribution plan employer matching contribution percent	5.00%

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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- Definition

Percentage employer matches of the employee's percentage contribution matched.

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- Definition

The annual vesting percentage of a defined contribution plan over the plan's vesting period.

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- Definition

The vesting period for a defined contribution plan.

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