Disclosures About Fair Value of Financial Instruments - Nonrecurring Assets that had Fair Market Values Below the Carrying Amount (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Level 1
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Loans individually assessed	$ 0	$ 0
Total financial assets	301,985	86,601
Level 2
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Loans individually assessed	0	0
Total financial assets	838,400	859,158
Level 3
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Loans individually assessed	8,751,479	8,666,149
Total financial assets	8,758,412	8,674,417
Fair Value, Measurements, Nonrecurring
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Real estate owned, net	1,075	950
Total financial assets	48,315	47,188
Fair Value, Measurements, Nonrecurring \| Level 1
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Real estate owned, net	0	0
Total financial assets	0	0
Fair Value, Measurements, Nonrecurring \| Level 2
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Real estate owned, net	0	0
Total financial assets	0	0
Fair Value, Measurements, Nonrecurring \| Level 3
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Real estate owned, net	1,075	950
Total financial assets	48,315	47,188
Loans measured for impairment \| Fair Value, Measurements, Nonrecurring
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Loans individually assessed	47,240	46,238
Loans measured for impairment \| Fair Value, Measurements, Nonrecurring \| Level 1
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Loans individually assessed	0	0
Loans measured for impairment \| Fair Value, Measurements, Nonrecurring \| Level 2
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Loans individually assessed	0	0
Loans measured for impairment \| Fair Value, Measurements, Nonrecurring \| Level 3
Fair value measurement for nonrecurring assets that had a fair market value below the carrying amount
Loans individually assessed	$ 47,240	$ 46,238

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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- Definition

Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(4))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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