Shareholder Report, Holdings (Details) - Master Small Cap Index Series

Jun. 30, 2026

Moog, Inc., Class A [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.40%

^[1],[2]

Hut 8 Corp. [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.40%

^[1],[2]

Viasat, Inc. [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.40%

^[1],[2]

BrightSpring Health Services, Inc. [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.40%

^[1],[2]

Cytokinetics, Inc. [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.30%

^[1],[2]

MaxLinear, Inc. [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.30%

^[1],[2]

Argan, Inc. [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.30%

^[1],[2]

UMB Financial Corp. [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.30%

^[1],[2]

JFrog Ltd. [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.30%

^[1],[2]

Riot Platforms, Inc. [Member]

Holdings [Line Items]

Percent of Net Asset Value

0.30%

^[1],[2]

Healthcare Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

19.80%

^[3]

Financial Services Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

17.70%

^[3]

Industrial Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

14.70%

^[3]

Information Technology Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

14.20%

^[3]

Consumer Discretionary Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

9.20%

^[3]

Energy Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

5.70%

^[3]

Real Estate Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

5.70%

^[3]

Materials Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

4.20%

^[3]

Utilities Sector [Member]

Holdings [Line Items]

Percent of Net Asset Value

2.70%

^[3]

Communication Services [Member]

Holdings [Line Items]

Percent of Net Asset Value

2.40%

^[3]

Other [Member]

Holdings [Line Items]

Percent of Net Asset Value

2.00%

^[3],[4]

Short-Term Securities [Member]

Holdings [Line Items]

Percent of Net Asset Value

11.00%

^[3]

Liabilities in Excess of Other Assets [Member]

Holdings [Line Items]

Percent of Net Asset Value

(9.30%)

^[3]

[1]	Excludes short-term securities.
[2]	Excludes underlying investments in equity swaps.
[3]	For purposes of this report, sector sub-classifications may differ from those utilized by the Series for compliance purposes.
[4]	Ten largest sectors are presented. Additional sectors are found in Other.