Loans - Activity in Portfolio (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Activity in allowance for loan losses
Allowance for loan losses at the beginning of the period	$ 6,029	$ 6,031	$ 3,984
Provision for loan losses	3,759	(2)	2,047
Allowance for loan losses at the end of the period	9,788	6,029	6,031
Recorded investment in loans related to the allowance for loan loss	516,450	401,880	294,767
Activity in loan portfolio
Balance at the beginning of the period	6,263,517	6,300,285	4,750,804
Acquisitions/origination/additional funding	4,502,842	4,223,178	4,820,464
Capitalized Interest	80,992	70,675	49,611
Basis of loans sold	(2,266,901)	(2,732,501)	(2,171,300)
Loan maturities/principal repayments	(2,742,462)	(1,647,852)	(1,244,445)
Discount accretion/premium amortization	48,384	36,862	21,287
Changes in fair value	74,251	64,320	70,420
Unrealized foreign currency remeasurement loss	(47,906)	(51,278)	(47,392)
Change in loan loss allowance, net	(3,759)	2	(2,047)
Transfer to/from other asset classifications	37,316	(174)	52,883
Balance at the end of the period	$ 5,946,274	$ 6,263,517	$ 6,300,285