diff --git a/parsl/jobs/strategy.py b/parsl/jobs/strategy.py
index 02af4dc207..032ba16d8c 100644
--- a/parsl/jobs/strategy.py
+++ b/parsl/jobs/strategy.py
@@ -3,12 +3,11 @@
 import time
 import math
 import warnings
-from typing import Dict, List, Optional
+from typing import Dict, List, Optional, TypedDict
 
 import parsl.jobs.job_status_poller as jsp
 
 from parsl.executors import HighThroughputExecutor
-from parsl.executors.base import ParslExecutor
 from parsl.executors.status_handling import BlockProviderExecutor
 from parsl.jobs.states import JobState
 from parsl.process_loggers import wrap_with_logs
@@ -17,6 +16,16 @@
 logger = logging.getLogger(__name__)
 
 
+class ExecutorState(TypedDict):
+    """Strategy relevant state for an executor
+    """
+
+    idle_since: Optional[float]
+    """The timestamp at which an executor became idle.
+    If the executor is not idle, then None.
+    """
+
+
 class Strategy:
     """Scaling strategy.
 
@@ -115,7 +124,7 @@ class Strategy:
 
     def __init__(self, *, strategy: Optional[str], max_idletime: float):
         """Initialize strategy."""
-        self.executors: Dict[str, ParslExecutor]
+        self.executors: Dict[str, ExecutorState]
         self.executors = {}
         self.max_idletime = max_idletime