Fair Values Measurements - Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans held-for-sale	$ 458,553	$ 91,202
Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available-for-sale	7,219,373	6,720,001
Loans held-for-sale	458,553	91,202
Recurring \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available-for-sale	0	0
Loans held-for-sale	0	0
Recurring \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available-for-sale	7,218,932	6,719,568
Loans held-for-sale	458,553	91,202
Recurring \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available-for-sale	441	433
Loans held-for-sale	0	0
Carrying Amount \| Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans held-for-sale	74,246	108,584
Net loans and leases	32,386,349	31,699,285
Securitization receivable	19,818	19,689
Deferred fees on commitments to extend credit	21,441	19,300
Total financial instrument assets	33,018,438	32,428,743
Certificates of deposits	7,142,996	7,455,556
Long-term borrowings	936,908	2,354,448
Deferred fees on standby letters of credit		56
Total financial instrument liabilities	8,079,904	9,810,060
Carrying Amount \| Recurring \| FHLB and FRB stocks
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available-for-sale	386,483	442,440
Carrying Amount \| Recurring \| Investment securities held-to-maturity
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available-for-sale	130,101	139,445
Estimated Fair Value \| Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans held-for-sale	77,633	112,525
Net loans and leases	32,701,958	31,804,513
Securitization receivable	19,690	19,466
Deferred fees on commitments to extend credit	21,441	19,300
Total financial instrument assets	33,348,312	32,543,088
Certificates of deposits	7,171,519	7,460,577
Long-term borrowings	940,617	2,368,469
Deferred fees on standby letters of credit		56
Total financial instrument liabilities	8,112,136	9,829,102
Estimated Fair Value \| Recurring \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans held-for-sale	0	0
Net loans and leases	0	0
Securitization receivable	0	0
Deferred fees on commitments to extend credit	0	0
Total financial instrument assets	0	0
Certificates of deposits	0	0
Long-term borrowings	0	0
Deferred fees on standby letters of credit		0
Total financial instrument liabilities	0	0
Estimated Fair Value \| Recurring \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans held-for-sale	75,746	110,252
Net loans and leases	0	0
Securitization receivable	0	0
Deferred fees on commitments to extend credit	21,441	19,300
Total financial instrument assets	621,105	713,160
Certificates of deposits	7,171,519	7,460,577
Long-term borrowings	940,617	2,368,469
Deferred fees on standby letters of credit		56
Total financial instrument liabilities	8,112,136	9,829,102
Estimated Fair Value \| Recurring \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans held-for-sale	1,887	2,273
Net loans and leases	32,701,958	31,804,513
Securitization receivable	19,690	19,466
Deferred fees on commitments to extend credit	0	0
Total financial instrument assets	32,727,207	31,829,928
Certificates of deposits	0	0
Long-term borrowings	0	0
Deferred fees on standby letters of credit		0
Total financial instrument liabilities	0	0
Estimated Fair Value \| Recurring \| FHLB and FRB stocks
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available-for-sale	386,483	442,440
Estimated Fair Value \| Recurring \| FHLB and FRB stocks \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available-for-sale	0	0
Estimated Fair Value \| Recurring \| FHLB and FRB stocks \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available-for-sale	386,483	442,440
Estimated Fair Value \| Recurring \| FHLB and FRB stocks \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available-for-sale	0	0
Estimated Fair Value \| Recurring \| Investment securities held-to-maturity
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available-for-sale	141,107	144,844
Estimated Fair Value \| Recurring \| Investment securities held-to-maturity \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available-for-sale	0	0
Estimated Fair Value \| Recurring \| Investment securities held-to-maturity \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available-for-sale	137,435	141,168
Estimated Fair Value \| Recurring \| Investment securities held-to-maturity \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available-for-sale	$ 3,672	$ 3,676

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Loans And Leases Receivable, Net, Fair Value Disclosure

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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The fair value amount of long-term debt 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.

+ References

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