Income Taxes - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Tax Contingency [Line Items]
Income tax benefit	$ 35,000	$ 21,000
State | Earliest Tax Year
Income Tax Contingency [Line Items]
Open tax year	Dec. 31, 2015
State | Latest Tax Year
Income Tax Contingency [Line Items]
Open tax year	Dec. 31, 2017
U.S. Federal Tax Authority | Earliest Tax Year
Income Tax Contingency [Line Items]
Open tax year	Dec. 31, 2015
U.S. Federal Tax Authority | Latest Tax Year
Income Tax Contingency [Line Items]
Open tax year	Dec. 31, 2017
California Tax Authority
Income Tax Contingency [Line Items]
Tax assessment additional period	5 years