protected function query_orders( $args ) {

		// set base query arguments
		$query_args = array(
			'fields'      => 'ids',
			'post_type'   => $this->post_type,
			'post_status' => array_keys( wc_get_order_statuses() ),
		);

		// add status argument
		if ( ! empty( $args['status'] ) ) {

			$statuses                  = 'wc-' . str_replace( ',', ',wc-', $args['status'] );
			$statuses                  = explode( ',', $statuses );
			$query_args['post_status'] = $statuses;

			unset( $args['status'] );

		}

		$query_args = $this->merge_query_args( $query_args, $args );

		return new WP_Query( $query_args );
	}