Long-term Debt (Narrative) (Details)	3 Months Ended
Mar. 31, 2019 Facility	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Long-term debt outstanding		$ 81,270,000	$ 75,115,000
Number of lease agreement under non-cancelable finance lease \| Facility	1
FHLB prepayment		0	25,000,000
FHLB prepayment penalty			165,000
FHLB fixed rate instruments, aggregate principal amounts due, 2022		70,271,000
FHLB fixed rate instruments, aggregate principal amounts due, 2023		6,784,000
FHLB fixed rate instruments, aggregate principal amounts due, 2024		299,000
FHLB fixed rate instruments, aggregate principal amounts due, 2025		313,000
FHLB fixed rate instruments, aggregate principal amounts due, 2026		221,000
FHLB fixed rate instruments, aggregate principal amounts due, thereafter		2,000
FHLB [Member]
Debt Instrument [Line Items]
Letter of credit outstanding, amount		$ 450,850,000	$ 288,950,000

Federal home loan bank advances penalty.

No definition available.

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- Definition

Federal home loan bank advances prepayment

+ References

No definition available.

+ Details

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- Definition

Number of lease agreement under non cancelable finance lease.

+ References

No definition available.

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No definition available.

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- Definition

Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

+ 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 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
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-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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- Definition

Amount of advance from Federal Home Loan Bank (FHLBank) maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
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-SubTopic 470
-Section 45
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- Definition

Amount of advance from Federal Home Loan Bank (FHLBank) maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of advance from Federal Home Loan Bank (FHLBank) maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of advance from Federal Home Loan Bank (FHLBank) maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of advance from Federal Home Loan Bank (FHLBank) maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
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- Definition

Amount of advance from Federal Home Loan Bank (FHLBank) maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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