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Fair Value Measurements (Summary of Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Beginning balance | $ 104,344 | $ 100,307
Total gains or losses (realized/unrealized) included in earnings | (6,922) | (820)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) | (2) | 246
Investment securities called | (2,000) | (4,635)
Discount accretion | 117 | 84
Purchases of private equity securities | 10,684 | 15,706
Sale / paydown of private equity securities | (364) | (6,548)
Capitalized interest/dividends | 29 | 32
Purchase of risk participation agreement | 0 | 439
Sale of risk participation agreement | (809) | (467)
Ending balance | 105,077 | 104,344
Total gains or losses for the annual period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at period end | (6,472) | (1,720)
Gains (Losses) included in OCI Attributable to Change in Unrealized Gains (Losses) Relating to Assets Still Held, Total | 44 | 0
State and Municipal Obligations [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Beginning balance | 9,853 | 14,158
Total gains or losses (realized/unrealized) included in earnings | 0 | 0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) | (2) | 246
Investment securities called | (2,000) | (4,635)
Discount accretion | 117 | 84
Purchases of private equity securities | 0 | 0
Sale / paydown of private equity securities | 0 | 0
Capitalized interest/dividends | 0 | 0
Purchase of risk participation agreement | 0 | 0
Sale of risk participation agreement | 0 | 0
Ending balance | 7,968 | 9,853
Total gains or losses for the annual period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at period end | 0 | 0
Gains (Losses) included in OCI Attributable to Change in Unrealized Gains (Losses) Relating to Assets Still Held, Total | 44 | 0
Private Equity Investments [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Beginning balance | 94,122 | 85,659
Total gains or losses (realized/unrealized) included in earnings | (10,103) | (727)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) | 0 | 0
Investment securities called | 0 | 0
Discount accretion | 0 | 0
Purchases of private equity securities | 10,684 | 15,706
Sale / paydown of private equity securities | (364) | (6,548)
Capitalized interest/dividends | 29 | 32
Purchase of risk participation agreement | 0 | 0
Sale of risk participation agreement | 0 | 0
Ending balance | 94,368 | 94,122
Total gains or losses for the annual period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at period end | (10,083) | (2,177)
Gains (Losses) included in OCI Attributable to Change in Unrealized Gains (Losses) Relating to Assets Still Held, Total | 0 | 0
Derivatives [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Beginning balance | 369 | 490
Total gains or losses (realized/unrealized) included in earnings | 3,181 | (93)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) | 0 | 0
Investment securities called | 0 | 0
Discount accretion | 0 | 0
Purchases of private equity securities | 0 | 0
Sale / paydown of private equity securities | 0 | 0
Capitalized interest/dividends | 0 | 0
Purchase of risk participation agreement | 0 | 439
Sale of risk participation agreement | (809) | (467)
Ending balance | 2,741 | 369
Total gains or losses for the annual period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at period end | 3,611 | 457
Gains (Losses) included in OCI Attributable to Change in Unrealized Gains (Losses) Relating to Assets Still Held, Total | $ 0 | $ 0

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