May 4 - Fitch Ratings has affirmed the Issuer Default Rating (IDR) and long-term ratings for IDEX Corporation (NYSE: IEX) at 'BBB+'. The Rating Outlook is Stable. A full ratings list is shown below. The ratings incorporate IEX's leading positions in a variety of niche markets, geographic diversification, strong operating margins and free cash flow, consistent financial policies, and steady operating performance through economic cycles. Leverage increased modestly following material a