General description of commitments which may be required in performing under a construction-type contract which are outside the ordinary course of business at the balance sheet date.

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Nominal or face amount used to calculate payments on the derivative liability.

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Describes the nature of any recourse provisions that would enable the guarantor to recover from third parties any of the amounts paid under the guarantee (or each group of similar guarantees).

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Commitments and Contingencies (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Sep. 22, 2015
Loss Contingencies [Line Items]
Derivative Liability, Notional Amount	$ 420,809	$ 153,593	$ 100,000
Commitments to Complete Contracts in Process	1374
Interest Rate Swap
Loss Contingencies [Line Items]
Derivative Liability, Notional Amount	$ 100,000
Mortgage Loans Held for Sale
Loss Contingencies [Line Items]
Guarantor Obligations, Recourse Provisions	999