Amid the rolling mountains surrounding this quiet town in southwest New York state, tucked away on miles-long stretches of underused rail tracks, hundreds of idle oil tank cars attest to the extent of fallout from oil’s rout. The oil tank cars – a year ago sought-after to haul crude from North Dakota to New Jersey – now stand idle as a result of two converging trends: the reversal in U.S. shale oil production and the completion of new pipelines.