Goodwill and intangible assets

3 Months Ended

Sep. 30, 2019

Goodwill and Intangible Assets Disclosure [Abstract]

The changes in the carrying amount of goodwill for the three months ended September 30, 2019 are as follows:



	Diversified Industrial Segment			Aerospace Systems Segment			Total
Balance at June 30, 2019	$	5,355,165		$	98,640		$	5,453,805
Acquisition	—			428,488			428,488
Foreign currency translation and other	(63,668		)	(12		)	(63,680		)
Balance at September 30, 2019	$	5,291,497		$	527,116		$	5,818,613

The acquisition line represents the goodwill allocation during the measurement period subsequent to the applicable acquisition date. Refer to Note 4 for further discussion.

Intangible assets are amortized on the straight-line method over their legal or estimated useful lives. The following summarizes the gross carrying value and accumulated amortization for each major category of intangible assets:



	September 30, 2019				June 30, 2019
	Gross Carrying Amount		Accumulated Amortization		Gross Carrying Amount		Accumulated Amortization
Patents and technology	$	600,411	$	132,896	$	265,644	$	130,233
Trademarks	627,253		255,674		542,573		252,388
Customer lists and other	2,957,091		1,102,429		2,435,461		1,077,780
Total	$	4,184,755	$	1,490,999	$	3,243,678	$	1,460,401

Total intangible amortization expense for the three months ended September 30, 2019 was $51,106. The estimated amortization expense for the five years ending June 30, 2020 through 2024 is $215,970, $222,107, $216,099, $205,156 and $199,597, respectively.

Intangible assets are evaluated for impairment whenever events or circumstances indicate that the undiscounted net cash flows to be generated by their use over their expected useful lives and eventual disposition may be less than their net carrying value. No material intangible asset impairments occurred during the three months ended September 30, 2019.