docs: function(arcs) {
  		var me = this;
  		var max = 0;
  		var chart = me.chart;
  		var i, ilen, meta, arc, controller, options, borderWidth, hoverWidth;
  
  		if (!arcs) {
  			// Find the outmost visible dataset
  			for (i = 0, ilen = chart.data.datasets.length; i < ilen; ++i) {
  				if (chart.isDatasetVisible(i)) {
  					meta = chart.getDatasetMeta(i);
  					arcs = meta.data;
  					if (i !== me.index) {
  						controller = meta.controller;
  					}
  					break;
  				}
  			}
  		}
  
  		if (!arcs) {
  			return 0;
  		}
  
  		for (i = 0, ilen = arcs.length; i < ilen; ++i) {
  			arc = arcs[i];
  			if (controller) {
  				controller._configure();
  				options = controller._resolveElementOptions(arc, i);
  			} else {
  				options = arc._options;
  			}
  			if (options.borderAlign !== 'inner') {
  				borderWidth = options.borderWidth;
  				hoverWidth = options.hoverBorderWidth;
  
  				max = borderWidth > max ? borderWidth : max;
  				max = hoverWidth > max ? hoverWidth : max;
  			}
  		}
  		return max;
  	}