Loans and Allowance for Loan Losses - Recorded Investment in Loans, Excluding Loans Acquired (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 14,425,260	$ 11,723,171
Loans, Excluding Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans individually evaluated for impairment	68,932	39,770
Loans collectively evaluated for impairment	9,561,144	8,390,618
Total Loans	9,630,076	8,430,388
Other Consumer and Other \| Loans, Excluding Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans individually evaluated for impairment	1,378	2,159
Loans collectively evaluated for impairment	466,282	318,180
Total Loans	467,660	320,339
Commercial \| Loans, Excluding Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans individually evaluated for impairment	36,079	13,062
Loans collectively evaluated for impairment	2,037,113	1,926,361
Total Loans	2,073,192	1,939,423
Real Estate \| Loans, Excluding Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans individually evaluated for impairment	31,093	24,253
Loans collectively evaluated for impairment	6,853,329	5,942,200
Total Loans	6,884,422	5,966,453
Consumer \| Loans, Excluding Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	396,748	405,470
Consumer \| Credit Card \| Loans, Excluding Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans individually evaluated for impairment	382	296
Loans collectively evaluated for impairment	204,420	203,877
Total Loans	$ 204,802	$ 204,173

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The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

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The balance of financing receivables that were individually evaluated for impairment.

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5074-111524

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