Horizontal Crack in Foundation
No, no, no, a horizontal crack COMPLETELY THROUGH your foundation wall on 3 sides of your house is not normal and is not acceptable...especially if you’re able to stick a dime in the crack...this is not just a “hairline” crack. 

I’ve designed hundreds and hundreds of concrete walls, slabs, etc. and NONE have cracked. People who have cracked foundations, slabs, etc. do not understand the difference between reinforcing rebar and temperature steel. 

I suspect your problem is one of the following issues


lack of vertical rebar for the load 
lack of temperature steel due to thickness of wall
contractor pouring a portion of the foundation wall up a ways (usually about half way) and then when they finish the pour they do not vibrate (consolidate) the two pours together by using a vibrator (contractors call it a stinger). This creates a “cold joint” between the two pours. 


This allows a small “hairline” crack that can grow due to movement of the building or water penetration into the joint and then freezing and expanding, etc. (if you live in a cold climate, I suspect this is the cause of your problem.)

If the wall is still level, (smart of you to check,) I doubt if it’s a structural problem (lack of vertical rebar). and I’d definitely seal the cracks to prevent bugs, water penetrating the crack...freezing and continuing to crack the wall further.