Subsequent Event	12 Months Ended
Dec. 31, 2021
Subsequent Events [Abstract]
Subsequent Event	Subsequent EventOn February 23, 2022, the Company announced that it has entered into an agreement for the sale of a real estate investment consisting of an office building located at 52 Lime Street, London, U.K. (known as “The Scalpel”) for £718 million, subject to agreed upon adjustments. The transaction is scheduled to close on March 7, 2022. The Company estimates that it will realize a pretax gain of more than $300 million in the first quarter of 2022, subject to adjustment for final transaction expenses and certain items, including the impact of the foreign exchange rate at the date of the close.

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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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