Idaho is about 1.2 times bigger than Cambodia.

Cambodia is approximately 181,035 sq km, while Idaho is approximately 214,314 sq km, making Idaho 18% larger than Cambodia. Meanwhile, the population of Cambodia is ~16.7 million people (15.1 million fewer people live in Idaho).
Tip: This to-scale comparison of Cambodia vs. Idaho uses the Mercator projection, which distorts the size of regions near the poles.