Subsequent Events	9 Months Ended
Sep. 30, 2019
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsOn October 21, 2019, we announced the commencement of a cash tender offer by our principal banking subsidiary, State Street Bank, for any and all of our $800 million aggregate principal amount of outstanding floating rate junior subordinated debentures due 2047. We also announced that we will redeem $50.1 million of our $150 million aggregate principal amount outstanding of floating rate junior subordinated deferrable interest debentures, Series A, due May 15, 2028, at a redemption price equal to the outstanding principal amount of the 2028 debentures to be redeemed, plus accrued and unpaid interest.

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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