8. REAL ESTATE

In December 2007, the Company closed the sale of its facility and associated real property for a purchase price of $109 million. Concurrent with the sale, the Company retired the entire $47.7 million in mortgage debt previously outstanding with respect to the facility and associated real property, and received cash of $61.0 million net of transaction costs and debt retirement.

Upon the closing of the sale of the facility and associated real property, the Company entered into a lease agreement (Lease) whereby it leased back for an initial term of 12 years its corporate headquarters comprised of two buildings located at 12790 El Camino Real (Front Building) and 12780 El Camino Real (Rear Building) in San Diego, California. The Company also entered into a series of lease amendments (Amendments), beginning in late 2008 through 2011, through which it vacated the Front Building, but continues to occupy the Rear Building. The ultimate result of this real estate sale was a net gain of $39.1 million which was deferred in accordance with authoritative guidance. The Company recognized $0.2 million and $0.9 million of the deferred gain during the three-month periods ending March 31, 2018 and 2017, and will recognize the remaining $8.6 million of the deferred gain on a straight-line basis over the amended Lease term which will expire at the end of 2029.

During 2017, the Company entered into an amendment to extend the current term of the Lease through December 31, 2029 (Term Amendment). Under the Term Amendment, the Company reduced its base rental rate by approximately 8% and will continue to pay base annual rent (subject to an annual fixed percentage increase), plus a 3.5% annual management fee, property taxes and other normal and necessary expenses associated with the Lease such as utilities, repairs and maintenance. Certain incentives were included in the Term Amendment, including approximately $13.1 million in various tenant improvement allowances, three months of rent abatement, and a reduction in the required security deposit amount from $4.7 million to $3.0 million. In lieu of a cash security deposit, Wells Fargo Bank, N.A. issued on the Company’s behalf a letter of credit in the amount of $3.0 million, which is secured by a deposit of equal amount with the same bank and is included in restricted cash on the Company’s condensed consolidated financial statements. The Company also has the right to extend the Lease for two consecutive ten-year terms as well as a right of first offer for future rental of adjacent office space owned by the landlord.

Historically, the Company had one sublease agreement for approximately 16,000 square feet of the Rear Building. This sublease resulted in approximately $0.3 million of rental income during the three months ended March 31, 2018 with this sublease rental income being recorded as an offset to rent expense. The income generated under this sublease is lower than the Company’s financial obligation under the Lease for the Rear Building, as determined on a per square foot basis. Consequently, at the inception of such a sublease, or in association with an amendment to such sublease, the Company is required to record a cease-use liability for the net present value of the estimated difference between the expected income to be generated under the sublease and future subleases and the Lease obligation over the remaining term of the Lease for the space that is occupied by the subtenant. The Company has reoccupied the space at the conclusion of the sublease in March 2018. The sublease termination resulted in reversal of cease use expense of approximately $0.5 million during the second quarter of 2017.

The following table sets forth changes to the accrued cease-use liability during the three months ended March 31, 2018 and 2017 (in thousands):

	Three Months Ended March 31,
	2018			2017
Beginning balance	$	62		$	853
Change in estimate		—			—
Payments		(62	)		(66	)
Ending balance	$	—		$	787