This script will run through all your AdWords accounts and store your data in a Google Spreadsheet.

mcc-account-reporting.js

/********************************************************************************
* This script will run through all your AdWords accounts and store your data in
* a Google Spreadsheet. 
*
* @author Russell Savage <russellsavage@gmail.com>
* @version 1.0
*
* THIS SOFTWARE IS PROVIDED BY Russell Savage ''AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL Russell Savage BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
********************************************************************************/
function main() {
  MccApp.accounts().withLimit(50).executeInParallel('runOnEachAccount', 'finished');
}

function runOnEachAccount() {
  Logger.log('Starting on: '+AdWordsApp.currentAccount().getCustomerId());
  var results = getAccountReport();
  Logger.log(results);
  return JSON.stringify(results);
}

function getAccountReport() {
  var OPTIONS = { includeZeroImpressions : true };
  var cols = getCols();
  var report = 'ACCOUNT_PERFORMANCE_REPORT';
  var query = ['select',cols.join(','),'from',report,
               'during','YESTERDAY'].join(' ');
  var reportIter = AdWordsApp.report(query, OPTIONS).rows();
  var resultsArray = [];
  while(reportIter.hasNext()) {
    var row = reportIter.next();
    for(var i in cols) {
      resultsArray.push(row[cols[i]]);
    }
  }
  return resultsArray;
}

function getCols() {
  return ['Date',
          'ExternalCustomerId',
          'AccountDescriptiveName',
          'Impressions',
          'Clicks',
          'Cost',
          'Conversions',
          'ConversionValue'
         ];
}

function getTotalsCols() {
  return ['Date',
          'Impressions',
          'Clicks',
          'Cost',
          'Conversions',
          'ConversionValue'];
}

function getSpreadsheet(name) {
  var fileIter = DriveApp.getFilesByName(name);
  var spreadsheet;
  if(fileIter.hasNext()) {
    spreadsheet = SpreadsheetApp.openById(fileIter.next().getId());
  } else {
    //create a new one
    spreadsheet = SpreadsheetApp.create(name);
  }
  return spreadsheet;
}

function addResultsToSpreadsheet(spreadsheet,accountResults,sheetName) {
  var sheet = getSheet(spreadsheet,sheetName,getCols());
  if(shouldAddRow(sheet,accountResults,getCols())) {
    sheet.appendRow(accountResults);
  }
}

function finished(resultsArray) {
  var spreadsheetName = 'MCC Account Report';
  var spreadsheet = getSpreadsheet(spreadsheetName);
  var totalResults;
  for(var i in resultsArray) {
    var accountResults = JSON.parse(resultsArray[i].getReturnValue());
    var sheetName = accountResults[getCols().indexOf('ExternalCustomerId')];
    if(!sheetName) { continue; }
    addResultsToSpreadsheet(spreadsheet,accountResults,sheetName);
    totalResults = addToTotalResults(totalResults,accountResults); 
  }
  var totalsSheetName = 'All Accounts';
  addResultsToSpreadsheet(spreadsheet,totalResults,totalsSheetName);
  if(spreadsheet.getSheetByName('Sheet1')) {
    spreadsheet.deleteSheet(spreadsheet.getSheetByName('Sheet1'));
  }
  Logger.log('Your results are: '+spreadsheet.getUrl());
}

function addToTotalResults(totalResults,accountResults) {
  if(!totalResults) { totalResults = ['',0,0,0,0,0]; }
  totalResults[getTotalsCols().indexOf('Date')] = 
    accountResults[getCols().indexOf('Date')];
  totalResults[getTotalsCols().indexOf('Impressions')] += 
    parseInt(accountResults[getCols().indexOf('Impressions')]);
  totalResults[getTotalsCols().indexOf('Clicks')] += 
    parseInt(accountResults[getCols().indexOf('Clicks')]);
  totalResults[getTotalsCols().indexOf('Cost')] += 
    parseFloat(accountResults[getCols().indexOf('Cost')]);
  totalResults[getTotalsCols().indexOf('Conversions')] += 
    parseFloat(accountResults[getCols().indexOf('Conversions')]);
  totalResults[getTotalsCols().indexOf('ConversionValue')] += 
    parseFloat(accountResults[getCols().indexOf('ConversionValue')]);
  return totalResults;
}

function shouldAddRow(sheet,results,cols) {
  var shouldAdd = true;
  var dates = sheet.getRange('A:A').getValues();
  for(var i in dates) {
    var dateStr = Utilities.formatDate(new Date(dates[i][0]),AdWordsApp.currentAccount().getTimeZone(),'yyyy-MM-dd');
    if(dateStr === results[cols.indexOf('Date')]) {
      return false;
    }
  }
  return true;
}

function getSheet(spreadsheet,sheetName,columns) {
  var sheet = spreadsheet.getSheetByName(sheetName);
  if(!sheet) {
    sheet = spreadsheet.insertSheet(sheetName);
    sheet.appendRow(columns);
  }
  return sheet;
}