Subsequent Events	12 Months Ended
Dec. 31, 2019
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events In 2020, we sold 35 buildings and land in Greensboro for an aggregate sale price of $193.4 million and expect to record aggregate gains on disposition of property of $105.0 million. On February 4, 2020, the Company declared a cash dividend of $0.48 per share of Common Stock, which is payable on March 10, 2020 to stockholders of record as of February 18, 2020.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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