John Hancock Investment Grade Bond Fund Investment Strategy - John Hancock Bond Trust Class NAV [Member] - John Hancock Investment Grade Bond Fund	May 31, 2026
Prospectus [Line Items]
Strategy [Heading]	<span style="color:#000000;font-family:Arial Narrow;font-size:10pt;font-weight:bold;">Principal investment strategies</span>
Strategy Narrative [Text Block]	Under normal market conditions, the fund invests at least 80% of its net assets (plus any borrowings for investment purposes) in investment-grade bonds (securities rated from AAA to BBB).These may include, but are not limited to, corporate bonds and debentures, mortgage-backed and asset-backed securities, U.S. government and agency securities, and U.S. dollar-denominated securities of foreign governments and corporations. The fund’s investment policies are based on credit ratings at the time of purchase. The fund may invest in bonds of any maturity, but normally maintains a dollar weighted average maturity of between three and ten years. The fund does not invest in bonds rated below investment grade at time of purchase. The manager focuses on sector allocation, industry allocation, and security selection in making investment decisions. When making sector and industry allocations, the manager uses top-down analysis to try to anticipate shifts in the business cycle. The manager uses bottom-up research to find individual securities that appear comparatively undervalued.The fund may engage in derivative transactions, including futures contracts and options which may be used to reduce risk, obtain efficient market exposure, and/or enhance investment returns. The fund’s investments in U.S. government and agency securities may or may not be supported by the full faith and credit of the United States. The fund may trade securities actively.

John Hancock Investment Grade Bond Fund Investment Strategy - John Hancock Bond Trust Class NAV [Member] - John Hancock Investment Grade Bond Fund

May 31, 2026

<span style="color:#000000;font-family:Arial Narrow;font-size:10pt;font-weight:bold;">Principal investment strategies</span>

Strategy Narrative [Text Block]

Under normal market conditions, the fund invests at least 80% of its net assets (plus any borrowings for investment purposes) in investment-grade bonds (securities rated from AAA to BBB).These may include, but are not limited to, corporate bonds and debentures, mortgage-backed and asset-backed securities, U.S. government and agency securities, and U.S. dollar-denominated securities of foreign governments and corporations. The fund’s investment policies are based on credit ratings at the time of purchase. The fund may invest in bonds of any maturity, but normally maintains a dollar weighted average maturity of between three and ten years. The fund does not invest in bonds rated below investment grade at time of purchase. The manager focuses on sector allocation, industry allocation, and security selection in making investment decisions. When making sector and industry allocations, the manager uses top-down analysis to try to anticipate shifts in the business cycle. The manager uses bottom-up research to find individual securities that appear comparatively undervalued.The fund may engage in derivative transactions, including futures contracts and options which may be used to reduce risk, obtain efficient market exposure, and/or enhance investment returns. The fund’s investments in U.S. government and agency securities may or may not be supported by the full faith and credit of the United States. The fund may trade securities actively.