Amount of gain (loss) from the difference between the sale price or salvage price and the book value of an asset that was sold or retired, and gain (loss) from the write down of assets from their carrying value to fair value.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Name:	us-gaap_GainLossOnSalesOfAssetsAndAssetImpairmentCharges
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Real Estate Transactions - Shoreline Technology Center (Details) - USD ($) $ in Thousands	1 Months Ended	6 Months Ended
	Nov. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Real Estate [Line Items]
Proceeds from sale of buildings		$ 0	$ 335,709
Shoreline Technology Center
Real Estate [Line Items]
Proceeds from sale of buildings	$ 1,000,000
Recognized gain on sale	$ 726,000