Loans Receivable and Allowance for Loan Losses - Accretable Yield Movement Schedule on Acquired Credit Impaired Loans in Center Merger (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance at beginning of period	$ 49,697	$ 55,002
Accretion	(23,874)	(21,837)
Changes in expected cash flows	12,330	16,532
Balance at end of period	$ 38,153	$ 49,697