We lease communications towers, ground, communications equipment, and dark fiber to tenants under operating leases. Our leases have initial lease terms ranging from five to 20 years, most of which includes options to extend or renew the leases for five to 80 years (based on the satisfaction of certain conditions as defined in the lease agreements), and some of which may include options to terminate the leases within one to six months. Certain lease agreements contain provisions for future rent increases. Payments due under the lease contracts include fixed payments plus, for some of our leases, variable payments.

The components of lease income for the three and nine months ended September 30, 2019 are as follows:

Lease payments to be received under non-cancellable operating leases where we are the lessor for the remainder of the lease terms are as follows:

(Thousands)	September 30, 2019⁽¹⁾		December 31, 2018⁽²⁾
2019	$	177,639	$	724,269
2020		730,486		693,596
2021		724,909		696,713
2022		727,167		699,561
2023		730,184		702,663
Thereafter		4,983,671		4,706,951
Total lease receivables	$	8,074,056	$	8,223,753
⁽¹⁾ Total future minimum lease payments to be received include $7.2 billion relating to the Master Lease with Windstream.
⁽²⁾ Prior period amounts have not been adjusted under the modified retrospective transition approach.

The underlying assets under operating leases where we are the lessor as of September 30, 2019 are summarized as follows:

(Thousands)	September 30, 2019
Land	$	27,392
Building and improvements		340,995
Real property interest		-
Poles		257,116
Fiber		2,801,312
Equipment		345
Copper		3,774,931
Conduit		89,770
Tower assets		146,401
Capital lease assets		32,660
Other assets		10,262
		7,481,184
Less: accumulated depreciation		(4,965,928	)
Underlying assets under operating leases, net	$	2,515,256

Depreciation expense for the underlying assets under operating leases where we are the lessor for the three and nine months ended September 30, 2019 is summarized as follows:

We have commitments under operating leases for communications towers, ground, colocation and dark fiber lease arrangements. We also have finance leases for dark fiber lease arrangements and other communications equipment. Our leases have initial lease terms ranging from less than one year to 30 years, most of which includes options to extend or renew the leases for less than one year to 85 years, and some of which may include options to terminate the leases within one to six months. Certain lease agreements contain provisions for future rent increases. Payments due under the lease contracts include fixed payments plus, for some of our leases, variable payments.

As of September 30, 2019, we have short term lease commitments amounting to approximately $1.8 million, for colocation and dark fiber arrangements.

The components of lease cost for the three and nine months ended September 30, 2019 are as follows:

(Thousands)	Three Months Ended September 30, 2019			Nine Months Ended September 30, 2019
Finance lease cost
Amortization of ROU assets	$	1,283		$	3,179
Interest on lease liabilities		1,571			3,192
Total finance lease cost		2,854			6,371
Operating lease cost		6,024			19,278
Short-term lease cost		522			1,451
Variable lease cost		47			304
Less sublease income		(2,479	)		(7,857	)
Total lease cost	$	6,968		$	19,547

Amounts reported in the Condensed Consolidated Balance Sheets for leases where we are the lessee as of September 30, 2019 were as follows:

(Thousands)	Location on Condensed Consolidated Balance Sheets	September 30, 2019
Operating leases
ROU asset, net	Other assets, net	$	112,579
ROU liability	Accounts payable, accrued expenses and other liabilities, net		112,365

Finance leases
ROU asset, gross	Property, plant and equipment, net	$	129,712
ROU liability	Finance lease obligations		55,225

Weighted-average remaining lease term
Operating leases		10.4 years
Finance leases		14.0 years

Weighted-average discount rate
Operating leases			9.8	%
Finance leases			8.0	%

(Thousands)	Nine Months Ended September 30, 2019
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from finance leases	$	3,192
Operating cash flows from operating leases		20,519
Financing cash flows from finance leases		3,179

Non-cash items:
New operating leases	$	23,706
New finance leases		3,240

Future lease payments under non-cancellable leases as of September 30, 2019 are as follows:

(Thousands)	Operating Leases			Finance Leases
2019	$	6,258		$	2,099
2020		24,159			7,598
2021		22,135			6,839
2022		19,650			6,708
2023		17,462			6,689
Thereafter		99,334			58,162
Total undiscounted lease payments	$	188,998		$	88,095
Less: imputed interest		(76,633	)		(32,870	)
Total lease liabilities	$	112,365		$	55,225

Future minimum rental payments under non-cancellable operating leases as of December 31, 2018⁽¹⁾ were as follows:

(Thousands)
2019	$	10,585
2020		7,543
2021		4,815
2022		3,186
2023		2,382
Thereafter		15,269
Total	$	43,780
⁽¹⁾ Prior period amounts have not been adjusted under the modified retrospective transition approach.

Future minimum rental payments under capital leases in effect as of December 31, 2018⁽¹⁾ were as follows:

(Thousands)
2019	$	8,683
2020		7,357
2021		6,638
2022		6,484
2023		6,457
Thereafter		52,533
Total minimum payments		88,152
Less amount representing interest		(32,870	)
Total	$	55,282
⁽¹⁾ Prior period amounts have not been adjusted under the modified retrospective transition approach.

(Thousands)	Sublease Rentals
2019	$	2,970
2020		9,431
2021		9,461
2022		9,493
2023		9,570
Thereafter		98,640
Total	$	139,565