Foreign Agency Obligations [Member] C000234047 [Member] Single Class Municipal Bonds [Member] Corporate Bond Securities [Member] C000234048 [Member] U S Government Sponsored Agency Securities [Member] U S Treasury Obligations [Member] C000234049 [Member] C000234050 [Member] Non Agency Mortgage Backed Securities [Member] C000234051 [Member] Asset-Backed Securities [Member] Commercial Paper [Member] Certificates of Deposit [Member] Money Market Funds [Member] C000253864 [Member] BlackRock Cash Funds Treasury SL Agency Shares [Member] U S Treasury Bills 4 32 07 14 26 [Member] U S Treasury Bills 4 40 06 02 26 [Member] U S Treasury Bills 4 00 08 14 26 [Member] U S Treasury Bills 3 79 08 24 26 [Member] U S Treasury Bills 4 03 02 19 27 [Member] U S Treasury Bills 3 98 08 10 26 [Member] U S Treasury Bills 4 05 11 13 26 [Member] U S Treasury Bills 3 75 02 05 27 [Member] U S Treasury Bills 3 90 09 14 26 [Member] Futures contracts net cumulative appreciation [Member] Liabilities in Excess of Other Assets [Member] Investment Type [Axis] Net Assets Investment Company Portfolio Turnover No Trading Symbol Flag