thick and thin
The American Heritage® Idioms Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
Examples from the Web for thick and thin
Historical Examples of thick and thin
Then you are a thick-and-thin supporter of the Government as it is.
The Works of Rudyard Kipling: One Volume EditionRudyard Kipling
The "thick-and-thin" loyalty never commended itself to me; it is too dog-like.
The Letters of Ambrose BierceAmbrose Bierce