| Label | Element | Value |
|---|---|---|
| Franklin Genomic Advancements ETF | Health Care [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Total Investments | oef_PctOfTotalInv | 96.50% |
| Franklin Genomic Advancements ETF | Materials [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Total Investments | oef_PctOfTotalInv | 2.80% |
| Franklin Genomic Advancements ETF | Information Technology [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Total Investments | oef_PctOfTotalInv | 0.70% |