The facets of Johnny Cash

JOHNNY CASH (r.) deserves every good thing that’s said about him, and there are many of them, in this new documentary.

Being that it’s authorized, it also includes a generous sampling of his music, which reinforces all those good things. Cash sang his style of American music as well as anyone has ever sung it, and he could switch effortlessly into whatever mood and tone each song demanded.

He could sing “Peace in the Valley,” “Sunday Morning Comin’ Down,” “Folsom Prison Blues” and “A Boy Named Sue” in the same show, and that versatility reflected his accommodating personality. Almost nobody could dislike Johnny Cash.

The only catch with “American Rebel” is that it hints at a more complex man than it portrays. If you wouldn’t call him “troubled,” at least later in life, you probably would still call him restless, and the documentary doesn’t delve into that part as deeply as some credible biographers have.

His son, John Carter Cash, says at one point that he knew his father very well, but never fully understood him.

It would be gratifying to see that unsettled side of him explored — not to get all trashy, but because presumably that was part of what shaped both the artist and the other sides of the man.

“American Rebel” doesn’t dodge well-documented matters like his pill addiction or his messy split from his first wife. It does skip over less successful parts of his career, like his last years at Sun Records. It devotes considerable time, wisely, to his mutual-admiration relationship with Bob Dylan.

It argues well that in Cash’s case, the overused word “icon” fits. It just leaves room, down the line, for a little further exploration.