What is the author's style in Buffett: The Making of an American Capitalist by Roger Lowenstein?

As Roger Lowenstein states, his interest in the study of Warren Buffett came about as an investor in Berkshire Hathaway and as a financial reporter for the Wall Street Journal. In these capacities, he hoped to mesh a familiarity with Buffett's personal and professional life and the objectivity of a reporter. In much of the work, this was accomplished. While Buffett himself refused to become involved or to be interviewed, he did not discourage others from doing so. Lowenstein was thus able to gain the personal perspectives and opinions of those closest to Buffett—family members, friends, and colleagues, in order to give the reader a relatively comprehensive picture of both the public and the private "oracle of Omaha."