Amount of investment in debt security measured at amortized cost, before allowance for credit losses.

No definition available.

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth 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).

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth 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).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through 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).

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through 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).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing after tenth 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).

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing after tenth 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).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

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Amount of investment in debt security measured at amortized cost (held-to-maturity).

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Securities - Securities Available-for-sale and Held-to-maturity by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Securities held-to-maturity, amortized cost, due after ten years	$ 50,832
Securities held-to-maturity, fair value, due after ten years	52,753
Securities held-to-maturity, amortized cost	58,731
Securities held-to-maturity, allowance for credit losses	(843)	$ (844)	$ (907)	$ (402)	$ (402)	$ (340)
Securities held-to-maturity, amortized cost	57,888		57,832
Securities held-to-maturity, fair value	61,451		63,529
Securities available for sale, amortized cost, due after one years through five years	20,000
Securities available for sale, fair value, due after one years through five years	19,932
Securities available for sale, amortized cost, due after five years through ten years	169,572
Securities available for sale, fair value, due after five years through ten years	167,957
Securities available for sale, amortized cost, due after ten years	12,207
Securities available for sale, fair value, due after ten years	12,193
Securities available for sale, amortized cost, total other securities	799,936		646,112
Securities available for sale, fair value, total other securities	796,799		647,974
US States and Political Subdivisions Debt Securities [Member]
Securities held-to-maturity, amortized cost	50,832		50,825
Securities held-to-maturity, fair value	52,753		54,538
Total Other Securities [Member]
Securities held-to-maturity, amortized cost	50,832
Securities held-to-maturity, fair value	52,753
Securities available for sale, amortized cost, total other securities	201,779
Securities available for sale, fair value, total other securities	200,082
Collateralized Mortgage Backed Securities [Member]
Securities held-to-maturity, amortized cost	7,899		7,914
Securities held-to-maturity, amortized cost	7,899		7,914
Securities held-to-maturity, fair value	8,698		8,991
Securities available for sale, amortized cost, total other securities	585,585		395,101
Securities available for sale, fair value, total other securities	584,145		404,460
Mutual Fund Debt Securities [Member]
Securities available for sale, amortized cost, total other securities	12,572		12,703
Securities available for sale, fair value, total other securities	$ 12,572		$ 12,703