Fair Value Measurements, Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Financial assets
Cash and due from banks	$ 334,095	$ 507,187
Interest-bearing deposits in other financial institutions	270,843	221,226
Federal funds sold and securities purchased under agreements to resell	41,405	148,285
Debt Securities, Held-to-maturity	2,846,689	2,740,511
Investment securities held to maturity, fair value	2,868,870	2,710,271
Investment securities available for sale	3,829,388	3,946,941
Equity securities with readily determinable fair values, Fair Value	1,609	1,568
FHLB and Federal Reserve Bank stocks	216,940	250,534
Residential Loans Receivable Held-for-sale, Net, Not Part of Disposal Group	81,392	64,321
Commercial Loans Held-for-sale, Fair Value Disclosure	15,467	14,943
Loans, net	22,913,278	22,702,406
Bank and Corporate Owned Life Insurance	665,976	663,203
Derivatives (trading assets)	77,920	88,943
Financial liabilities
Short-term funding	159,117	157,074
Other long-term funding	796,007	795,611
Derivatives (trading liabilities)	77,859	87,668
Letters of Credit Outstanding, Amount	256,000	256,000
Fair Value, Inputs, Level 1
Financial assets
Cash and due from banks	334,095	507,187
Cash and due from banks, Fair Value	334,095	507,187
Interest-bearing deposits in other financial institutions	270,843	221,226
Interest-bearing deposits in other financial institutions, fair value	270,843	221,226
Federal funds sold and securities purchased under agreements to resell	41,405	148,285
Federal funds sold and securities purchased under agreements to resell, fair value	41,405	148,285
Debt Securities, Held-to-maturity	999	0
Investment securities held to maturity, fair value	1,007	0
Investment securities available for sale	0	999
Investment securities available for sale, fair value	0	999
Equity securities with readily determinable fair value, Carrying Amount	1,609	1,568
Equity securities with readily determinable fair values, Fair Value	1,609	1,568
Fair Value, Inputs, Level 2
Financial assets
Debt Securities, Held-to-maturity	2,845,690	2,740,511
Investment securities held to maturity, fair value	2,867,864	2,710,271
Investment securities available for sale	3,829,388	3,945,943
Investment securities available for sale, fair value	3,829,388	3,945,943
FHLB and Federal Reserve Bank stocks	216,940	250,534
FHLB and Federal Reserve Bank stocks, fair value	216,940	250,534
Residential Loans Receivable Held-for-sale, Net, Not Part of Disposal Group	81,392	64,321
Residential Held-for-sale, Fair Value Disclosure	81,392	64,321
Commercial loans held for sale	15,467	14,943
Commercial Loans Held-for-sale, Fair Value Disclosure	15,467	14,943
Bank and Corporate Owned Life Insurance	665,976	663,203
Bank owned life insurance, fair value	665,976	663,203
Financial liabilities
Brokered CDs and other time deposits	3,751,665	2,815,401
Brokered CDs and other time deposits, fair value	3,751,665	2,815,401
Short-term funding	179,117	1,057,074
Short-term funding, fair value	179,117	1,057,074
Other long-term funding	3,720,776	3,469,982
Long-term funding, fair value	3,761,004	3,492,174
Standby letters of credit	2,478	2,482
Standby letters of credit, fair value	2,478	2,482
Fair Value, Inputs, Level 3
Financial assets
Loans, net	22,913,278	22,702,406
Loans, net, fair value	22,626,091	22,317,395
Derivatives (trading assets)	3,032	2,208
Derivatives (trading and other assets), fair value	3,032	2,208
Financial liabilities
Noninterest-bearing demand, savings, interest-bearing demand, and money market accounts	21,781,392	22,081,992
Noninterest-bearing demand, savings, interest-bearing demand, and money market deposits, fair value	21,781,392	22,081,992
Derivatives (trading liabilities)	1,825	2,072
Derivatives (trading and other liabilities), fair value	1,825	2,072
Trading Assets [Member] \| Fair Value, Inputs, Level 2
Financial assets
Derivatives (trading assets)	77,920	88,943
Derivatives (trading and other assets), fair value	77,920	88,943
Other Assets [Member] \| Fair Value, Inputs, Level 2
Financial assets
Derivatives (trading assets)	156	109
Derivatives (trading and other assets), fair value	156	109
Trading Liabilities [Member] \| Fair Value, Inputs, Level 2
Financial liabilities
Derivatives (trading liabilities)	77,859	87,668
Derivatives (trading and other liabilities), fair value	77,859	87,668
Other Liabilities [Member] \| Fair Value, Inputs, Level 2
Financial liabilities
Derivatives (trading liabilities)	284	149
Derivatives (trading and other liabilities), fair value	$ 284	$ 149

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

No definition available.