401(k) Plan	12 Months Ended
	Dec. 31, 2019
Retirement Benefits [Abstract]
401(k) Plan	401(k) PlanThe Company offers the Upwork Retirement Savings Plan (the “Retirement Plan”), a defined contribution plan that allows employees to contribute a portion of their salary, subject to the annual limits. Under the Retirement Plan, eligible employees may defer a portion of their pretax salaries, but not more than the statutory limits. The Retirement Plan provides for a discretionary employer cash matching contribution. The Company makes matching cash contributions equal to 50% of each dollar contributed, subject to a maximum contribution of $5,000 annually per participant. The Company’s total expense for the matching contributions was $2.0 million, $1.7 million and $1.2 million for the years ended December 31, 2019, 2018 and 2017, respectively.