Collateralized Receivables and Transfers of Financial Assets, Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes and other receivables, net	$ 81,179	$ 47,972
Secured debt	2,819,567	2,125,267
Secured Debt [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Secured debt	3,110,042	2,336,297
Collateralized Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Allowance	$ 607	$ 672	$ 688
Receivable with Imputed Interest, Effective Yield (Interest Rate)	10.00%	10.20%
Receivable With Imputed Interest, Term	15 years 8 months 12 days	15 years 7 months 6 days
Interest Income (Expense), Net	$ 14,000	$ 13,200	$ 11,800
Reported Value Measurement [Member] | Secured Debt [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Secured debt	144,477	140,440
Reported Value Measurement [Member] | Collateralized Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes and other receivables, net	$ 143,870	$ 139,768