I went to type "mainline denominations" into Google a few moments ago. Here's what came up as Google's first suggestion:
This is problematic.
Here's a series of articles I've written on why we should take this stuff seriously:
Killing Church Committees and Other Reflections on Church Organization
Taming the Chihuahua Brain
Killing the Whispers and Other Reflections on Church Decision-Making
Crack Addiction and Church Transformation