conceptual; idealistic
Describes something based on abstract principles or ideals rather than practical considerations. Often used in formal or philosophical contexts.
His proposal is conceptually wonderful, but difficult to realize.
This organization advocates idealistic goals.
理想的 means 'ideal' in the sense of perfect or most desirable, whereas 理念的 refers to being based on a principle or ideology.
Derived from 理念 (principle, ideal) + 的 (-like, -ic). The base 理念 is a Sino-Japanese compound of 理 (reason, principle) and 念 (thought, sense).