Loans - Activity in Portfolio (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Activity in allowance for loan losses
Allowance for loan losses at the beginning of the period			$ 39,151	$ 4,330
Provision for (reversal of) loan losses			(3,281)	3,055
Provision for impaired loans				29,852
Charge-offs			(9,126)
Allowance for loan losses at the end of the period	$ 33,306	$ 31,127	33,306	31,127
Recorded investment in loans related to the allowance for loan loss	303,981	273,020	303,981	273,020
Activity in loan portfolio
Balance at the beginning of the period			9,794,254	7,382,641
Acquisitions/origination/additional funding			3,704,727	3,315,664
Capitalized Interest			52,405	29,499
Basis of loans sold			(1,767,387)	(676,214)
Loan maturities/principal repayments			(1,447,593)	(1,964,644)
Discount accretion/premium amortization			16,112	20,961
Changes in fair value	21,891	14,833	33,157	22,633
Unrealized foreign currency translation (loss) gain			(3,903)	(8,608)
Loan loss provision, net			(3,281)	(26,797)
Loan foreclosure			(27,303)
Transfer to/from other asset classifications			(73)	27
Balance at the end of the period	$ 10,351,115	$ 8,095,162	$ 10,351,115	$ 8,095,162