General form of registration statement for all companies including face-amount certificate companies

Fair Value Measurements - Summary of financial assets measured at fair value on a recurring bases (Details)

v3.21.2
Fair Value Measurements - Summary of financial assets measured at fair value on a recurring bases (Details) - Fair Value, Recurring [Member] - USD ($)
$ in Thousands
Jun. 30, 2021
Dec. 31, 2020
Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Total cash equivalents $ 783,108 $ 387,464 $ 246,521
Level 1 [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Total cash equivalents 783,108 387,464 196,519
Money Market Funds [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Total cash equivalents 783,108 387,464 196,519
Money Market Funds [Member] | Level 1 [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Total cash equivalents $ 783,108 $ 387,464 $ 196,519