Parent Company Only Financial Information, Balance Sheet (Details) - USD ($) $ in Thousands		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Assets
Cash and due from banks		$ 416,154	$ 373,380
Interest-bearing deposits in other financial institutions		298,759	207,624
Other assets	[1]	653,219	506,046
Total assets		33,419,783	32,386,478
Liabilities and Stockholders' Equity
Commercial paper		59,346	32,016
Subordinated notes, at par		250,000	250,000
Long-term funding capitalized costs		1,663	2,866
Total long-term funding		549,465
Other Liabilities		364,088	467,961
Total liabilities		29,328,850	28,464,355
Preferred equity		353,512	256,716
Common equity		1,752	1,752
Total stockholders’ equity		4,090,933	3,922,124	$ 3,780,888	$ 3,237,443
Total liabilities and stockholders’ equity		33,419,783	32,386,478
Parent Company Only
Assets
Cash and due from banks		40,204	17,427
Interest-bearing deposits in other financial institutions		15,228	27,186
Notes and interest receivable from subsidiaries		305,779	201,551
Investments in and receivable due from subsidiaries		4,005,198	3,925,596
Other assets		46,850	46,234
Total assets		4,413,259	4,217,994
Liabilities and Stockholders' Equity
Commercial paper		59,346	32,016
Subordinated notes, at par		250,000	250,000
Long-term funding capitalized costs		(1,133)	(1,428)
Total long-term funding		248,867	248,572
Other Liabilities		14,113	15,282
Total liabilities		322,326	295,870
Preferred equity		353,512	256,716
Common equity		3,737,421	3,665,407
Total stockholders’ equity		4,090,933	3,922,124
Total liabilities and stockholders’ equity		$ 4,413,259	$ 4,217,994

[1] (a) See Note 1 Summary of Significant Accounting Policies for additional details on the adoption of ASU 2016-13.