Notes and Loan Payable (Line of Credit Narrative) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2016 USD ($) banks occasions guarantor
Line of Credit Facility [Line Items]
Term loan	$ 100,000
2016 Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of credit, number of banks in agreement | banks	6
Line of credit, maximum borrowing capacity	$ 150,000
Line of credit, interest rate, floating, applicable margin	0.75%
Line of credit, interest rate, floating, adjusted LIBOR	1.75%
Line of credit, unused capacity, commitment fee percentage	0.275%
Minimum risk-based capital ratio	275.00%
Maximum debt to capital ratio	0.35
Minimum capital to be retained	80.00%
Minimum portion of net income to be retained	50.00%
Minimum capital contributions to be retained	50.00%
Line of credit, number of occasions borrowing capacity can be increased | occasions	3
Line of credit, additional borrowing capacity, aggregate amount	$ 50,000
Line of credit, maturity date extension available, years	1 year
Line of credit, number of guarantors | guarantor	0
Line of credit, amount outstanding	$ 0
Cash in excess of amount required by covenants	$ 445,000
2013 Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of credit, number of banks in agreement | banks	5
Line of credit, maximum borrowing capacity	$ 140,000