Securities Securities (Summary of Gross Realized Gains and Gross Realized Losses (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2020		Jun. 30, 2019	Jun. 30, 2020		Jun. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Proceeds from Sale of Debt Securities, Available-for-sale	$ 0		$ 175,586	$ 194,105		$ 259,554
Gross Realized Gains from sales of debt securities available for sale	0		1,510	435		3,357
Gross Realized Losses from sales of debt securities available for sale	0		(1,225)	(186)		(1,225)
Other securities gains	16,425	[1],[2]	0	16,425	[1],[2]	0
Investment securities gain (loss), net	$ 16,425		$ 285	$ 16,674		$ 2,132

[1] Other securities gains includes gain from sale of Visa Class B restricted stock and subsequent write up to fair value of remaining Visa Class B shares.

[2] Visa Class B restricted stock owned by the Company was previously carried at a zero-cost basis due to existing transfer restrictions and uncertainty of covered litigation. The sale of shares by the Company of Visa Class B restricted shares during the three months ended June 30, 2020 resulted in an observable market price. As a result, the Company adjusted the carrying value of its remaining shares of Visa Class B restricted shares upward to this observable market price.