How can I remove extra whitespace from the bottom of a line chart in chart.js?

As you can see below with the canvas element highlighted, there is considerable whitespace below the x axis label. If I resize the canvas, the whitespace stays proportional to the height of it. Are there any settings that control this whitespace? I've ruled out padding and do not see any settings for margins.

Thanks!

Here is the JavaScript that renders the chart:

var ctx = document.getElementById("myChart");
var myChart = new Chart(ctx, {
  options: {
    legend: {
      display: false
    },
    elements: {
      point: {
        radius: 0
      }
    },
    scales: {
      xAxes: [{
        gridLines: {
          display: false,
          drawBorder: true
        },
        ticks: {
          autoSkip: true,
          maxTicksLimit: 1
        }
      }],
      yAxes: [{
        gridLines: {
          display: true,
          drawBorder: false
        },
        ticks: {
          callback: function(value, index, values) {
            return '$' + addCommas(value);
          }
        }
      }]
    },
    layout: {
      padding: 5
    }
  },
  type: 'line',
  data: {
    labels: labels,
    datasets: [
      { 
        data: values,
        fill: false,
        borderColor: "blue"
      }
    ]
  }
});

And the complete jsfiddle: https://jsfiddle.net/rsn288fh/2/