A detent escapement includes an escape wheel with teeth regularly spaced along a perimeter and a balance having an impulse pallet and receiving driving impulses via the teeth, the balance performing an alternation during which it receives a driving impulse and an alternation without a driving impulse, the detent escapement also including a hook pivotally mounted on the balance and held bearing by an elastic member against an abutment, the detent escapement including a pivotable detent which includes a first arm which collaborates with the escape wheel to block the latter before the start of the driving impulse, as well as a second arm to allow the escape wheel to disengage from its engagement with the first arm at the start of the driving impulse, and which limits the pivoting of this detent to only part of the oscillation of the balance, the detent being configured to again block the escape wheel after the latter has finished providing the driving impulse to the impulse pallet of the balance.