Dispositions and Assets Held for Sale

We periodically sell properties for various reasons, including favorable market conditions, the exercise of tenant purchase options or reduction of concentrations (e.g., property type, relationship or geography). At June 30, 2018, 35 triple-net, 18 seniors housing operating and two outpatient medical properties with an aggregate real estate balance of $547,321,000 were classified as held for sale. During the six months ended June 30, 2018, we recorded impairment charges of $32,817,000 on certain held for sale properties for which the carrying values exceeded the fair values, less estimated costs to sell if applicable. The following is a summary of our real property disposition activity for the periods presented (in thousands):



	Six Months Ended
	June 30, 2018		June 30, 2017
Real estate dispositions:
Triple-net	$	367,978	$	882,436
Seniors housing operating	2,200		13,845
Outpatient medical	223,069		—
Total dispositions	593,247		896,281
Gain (loss) on real estate dispositions, net	348,939		286,247
Net other assets/liabilities disposed	5,032		21,254
Proceeds from real estate dispositions	$	947,218	$	1,203,782

Dispositions and Assets Held for Sale

Pursuant to our adoption of ASU No. 2014-08, “Presentation of Financial Statements (Topic 205) and Property, Plant and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity”, operating results attributable to properties sold subsequent to or classified as held for sale after January 1, 2014 and which do not meet the definition of discontinued operations are no longer reclassified on our Consolidated Statements of Comprehensive Income. The following represents the activity related to these properties for the periods presented (in thousands):



	Three Months Ended June 30,				Six Months Ended June 30,
	2018		2017		2018		2017
Revenues:
Total revenues	$	35,236	$	60,241	$	78,459	$	135,348
Expenses:
Interest expense	120		1,540		264		4,266
Property operating expenses	22,364		22,365		45,516		46,606
Provision for depreciation	2,555		12,455		6,874		24,749
Total expenses	25,039		36,360		52,654		75,621
Income (loss) from real estate dispositions, net	$	10,197	$	23,881	$	25,805	$	59,727