Summary of Significant Accounting Policies (Reconciliation of Common Shares Outstanding to Diluted) (Details) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Schedule of Reconciliation of the Weighted Average Common Shares Outstanding [Line Items]
Basic (in shares)	82,058	65,767	81,802	65,479
Diluted (in shares)	83,853	65,908	83,240	65,866
Restricted Stock Awards And Units [Member]
Schedule of Reconciliation of the Weighted Average Common Shares Outstanding [Line Items]
Incremental Common Shares Attributable to Dilutive Effect of Nonvested Shares with Forfeitable Dividends	833	141	640	387
Performance Shares [Member]
Schedule of Reconciliation of the Weighted Average Common Shares Outstanding [Line Items]
Incremental Common Shares Attributable to Dilutive Effect of Nonvested Shares with Forfeitable Dividends	134	0	158	0
Warrant [Member]
Schedule of Reconciliation of the Weighted Average Common Shares Outstanding [Line Items]
Incremental Common Shares Attributable to Dilutive Effect of Call Options and Warrants	828	0	640	0