Leases
 12 Months Ended
Dec. 31, 2015
Leases [Abstract]  
Leases
Leases
The Company has non-cancelable operating leases, primarily for land, tower space, office-space, certain office equipment and vehicles. The operating leases generally contain renewal options for periods ranging from one to ten years and require the Company to pay all executory costs such as maintenance and insurance. Rental expense for operating leases was approximately $27.9 million, $27.4 million, and $22.6 million for the years ended December 31, 2015, 2014 and 2013, respectively.
Future minimum payments under non-cancelable operating leases (with initial or remaining lease terms in excess of one year), future minimum sublease income to be received and a lease commitment under a sale leaseback agreement as of December 31, 2015 are as follows (in thousands):
Year Ending December 31:
 
Future Minimum Rent Under Operating Leases
 
Future Minimum Sublease Income
 
Future Minimum Commitments Under Sale Leaseback Agreement
 
Net Commitments
2016
 
$
25,455

 
$
(269
)
 
$
1,076

 
$
26,262

2017
 
22,385

 
—

 
1,114

 
23,499

2018
 
17,686

 
—

 
1,153

 
18,839

2019
 
14,444

 
—

 
1,193

 
15,637

2020
 
10,478

 
—

 
—

 
10,478

Thereafter
 
27,021

 
—

 
—

 
27,021

 
 
$
117,469

 
$
(269
)
 
$
4,536

 
$
121,736