private com.google.protobuf.SingleFieldBuilderV3<
            com.google.protobuf.Duration,
            com.google.protobuf.Duration.Builder,
            com.google.protobuf.DurationOrBuilder>
        getIdleDurationFieldBuilder() {
      if (idleDurationBuilder_ == null) {
        idleDurationBuilder_ =
            new com.google.protobuf.SingleFieldBuilderV3<
                com.google.protobuf.Duration,
                com.google.protobuf.Duration.Builder,
                com.google.protobuf.DurationOrBuilder>(
                getIdleDuration(), getParentForChildren(), isClean());
        idleDuration_ = null;
      }
      return idleDurationBuilder_;
    }
<pre>
The idle duration between replication stages.
</pre>

<code>.google.protobuf.Duration idle_duration = 1;</code>
java-vmmigration/proto-google-cloud-vmmigration-v1/src/main/java/com/google/cloud/vmmigration/v1/SchedulePolicy.java