Explain in details, the differences between the IFRS and GAAP (after FASB issued ASU 2017-04 to simplify the accounting for goodwill impairment) regarding the following:

1. Assignment/allocation of goodwill. (i.e. The levels at which goodwill is assigned /allocated)
2. Impairment of goodwill and test(s) applied and its steps (i.e. Methods of determining impairment of goodwill)
3. How impairment loss is recognized and allocated.(i.e. impairment loss[charge] calculation and allocation)
4. Amortization and impairment of intangible assets other than goodwill

Answer this question in a tabular format, like the following one:

	IFRS	GAAP
Assignment/allocation of goodwill
Impairment of goodwill
How impairment loss is recognized and allocated
Amortization and impairment of intangible assets other than goodwill

(You must support your answer in this question with quality and up to date references.)