Debt (Details)	3 Months Ended			12 Months Ended			13 Months Ended						12 Months Ended
	Dec. 31, 2013 USD ($)	Mar. 31, 2013 USD ($)	Sep. 30, 2012 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2005 CAD	Jan. 08, 2009	Sep. 30, 2013 USD ($)	Dec. 31, 2010	Dec. 31, 2009	Jul. 14, 2005 CAD	Jan. 23, 2004 USD ($)	Dec. 31, 2013 Senior Notes [Member] USD ($)	Dec. 31, 2012 Senior Notes [Member] CAD	Dec. 31, 2012 Senior Notes [Member] USD ($)	Dec. 31, 2013 Preferred Units, Class [Domain] CAD	Dec. 31, 2012 Unsecured Debt [Member] USD ($)	Dec. 31, 2013 Subordinated Debt [Member] USD ($)	Dec. 31, 2012 Subordinated Debt [Member] USD ($)	Dec. 31, 2013 Maximum [Member]	Dec. 31, 2013 Maximum [Member] Senior Notes [Member]	Dec. 31, 2013 Minimum [Member]
Debt Instrument [Line Items]
Senior unsecured debentures. at fair value	$ 14,356,000			$ 14,356,000	$ 23,730,000							$ 100,000,000	$ 14,356,000
Debt Instrument, Interest Rate, Stated Percentage					6.00%						5.00%	0.00%								0.00%		0.00%
Debt Instrument, Increase (Decrease), Net		25,000,000
Interest				5,145,000	4,487,000								2,200,000	2,000,000
Early Repayment of Senior Debt	12,000,000	600,000
Debt Instrument, Repurchased Face Amount		600,000
Debt Instrument, Repurchase Amount		600,000
Proceeds from (Repayments of) Debt		0
Increase (Decrease) in Interest Payable, Net	200,000
Debt Instrument, Principal Value	119,710,000			119,710,000	133,345,000										26,966,000			90,500,000	90,500,000
Long-term Debt	57,681,000			57,681,000	61,159,000												100,000,000
Proceeds from Issuance of Debt			99,200,000
Repayments of Long-term Debt			1,700,000
Debt, Weighted Average Interest Rate	0.00%			0.00%									0.00%							0.00%	0.00%
Proceeds from Issuance of Long-term Debt						74,100,000
LROC preferred units	2,333,715			2,333,715					1,500,000	750,000
LROC preferred price per unit									20.0	17.5
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	0.00%			0.00%
Subordinated debt, at fair value	28,471,000			28,471,000	23,774,000			0								15,800,000
LROC preferred units, at fair value	14,854,000			14,854,000	13,655,000						78,000,000
LROC Preferred Units Tendered									1,525,150
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum							0.00%
Interest Payable	$ 12,800,000			$ 12,800,000