Idaho is about 42 times bigger than Delaware.

Delaware is approximately 5,060 sq km, while Idaho is approximately 214,314 sq km, making Idaho 4,135% larger than Delaware. Meanwhile, the population of Delaware is ~897,934 people (669,648 more people live in Idaho).
Tip: This to-scale comparison of Delaware vs. Idaho uses the Mercator projection, which distorts the size of regions near the poles.