Fair Value Measurements - Level 3 Inputs (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans receivable	$ 757,064	$ 761,023

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Glossary Loan
-URI http://asc.fasb.org/extlink&oid=6517073

Name:	us-gaap_LoansReceivableFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant