Property and Equipment, net

12 Months Ended

Sep. 30, 2018

Property Plant And Equipment [Abstract]

6.	Property and Equipment

Property and equipment, net consists of the following:

	Useful Life		September 30, 2018		September 30, 2017
Land		—	$	51,490	$	37,225
Buildings and leasehold improvements	2-40 yrs.			36,275		27,652
Operating equipment	2-7 yrs.			186,499		182,720
Transportation vehicles	3-7 yrs.			208,371		174,434
Office equipment and software	3-10 yrs.			57,976		47,042
Construction in progress		—		4,202		4,639
Property and equipment				544,813		473,712
Less: Accumulated depreciation				288,007		228,178
Property and equipment, net			$	256,806	$	245,534

Construction in progress includes costs incurred for software and other assets that have not yet been placed in service. Depreciation expense related to property and equipment was $75,296, $56,473 and $79,255 for the year ended September 30, 2018, the nine months ended September 30, 2017 and the year ended December 31, 2016, respectively.

Included in accumulated depreciation shown above are amounts related to property and equipment under capital leases of $22,244 and $18,200 at September 30, 2018 and September 30, 2017, respectively.