Equity - Capital Requirements (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Equity [Abstract]
Capital required for capital adequacy	$ 572,926,000	$ 544,984,000
Capital	742,000,000	727,600,000
Excess capital	$ 169,100,000	$ 182,600,000

The amount of total capital as defined in the regulations.

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