Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Additional Information (Details)

v3.19.3
Fair Value Measurements - Additional Information (Details) - USD ($)
9 Months Ended 12 Months Ended
Sep. 30, 2019
Sep. 30, 2018
Dec. 31, 2018
Fair Value Disclosures [Abstract]      
Fair value, assets, level 1 to level 2 transfers, amount $ 0 $ 0 $ 0
Fair value, assets, level 2 to level 1 transfers, amount 0 0 0
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, transfers, net $ 0 $ 0 $ 0