Consolidated Statements Of Cash Flows - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
CASH FLOWS FROM OPERATING ACTIVITIES      
Net income (loss) $ 33,718 $ 130,294 $ (142,052)
Adjustments to reconcile net income to net cash provided by Operating activities:      
Depreciation and amortization, including related intangible assets 198,674 186,549 172,108
Amortization of directors deferred compensation stock units 482 372 397
Amortization of stock compensation 7,447 5,646 2,219
Amortization of deferred financing costs 4,612 4,582 3,790
Amortization of debt discount and mark-to-market (287) 1,686 3,385
Equity in (earnings) loss of unconsolidated joint ventures [1] 6,081 (18,788) 3,172
Distributions of cumulative earnings from unconsolidated joint ventures 8,186 6,120 5,644
Gain on change of control of interests   (15,347)  
Realized (gains) losses and unrealized losses on disposition of rental property, net (2,364) (109,666) (53,261)
Gain on sale of investments in unconsolidated joint ventures (23,131) (5,670) (6,448)
Loss (gain) from extinguishment of debt 421 (12,420)
Impairments     197,919
Changes in operating assets and liabilities:      
Increase in unbilled rents receivable, net (11,286) (12,775) (1,760)
Increase in deferred charges, goodwill and other assets (19,711) (33,878) (22,854)
Decrease (increase) in accounts receivable, net 2,831 596 (2,178)
Increase (decrease) in accounts payable, accrued expenses and other liabilities (9,012) (14,535) 6,960
Decrease in rents received in advance and security deposits (1,817) (3,297) (2,408)
Increase (decrease) in accrued interest payable 1,296 (9,362) 4,822
Net cash provided by operating activities 196,140 100,107 169,455
CASH FLOWS FROM INVESTING ACTIVITIES      
Rental property acquisitions and related intangibles (619,350) (407,869) (70,455)
Rental property additions and improvements (90,068) (121,582) (94,073)
Development of rental property and other related costs (267,845) (206,955) (81,073)
Proceeds from the sales of rental property 311,923 607,457 81,049
Proceeds from the sale of investments in unconsolidated joint ventures 110,269 6,420 6,448
Investments in notes receivable (47,049)    
Repayment of notes receivable 74,945 500 8,250
Investment in unconsolidated joint ventures (36,060) (35,930) (78,027)
Distributions in excess of cumulative earnings from unconsolidated joint ventures 5,877 22,231 6,445
Proceeds from investment receivable 3,625    
Decrease (increase) in restricted cash 8,027 (1,934) (1,098)
Net cash provided by investing activities (545,706) (137,662) (222,534)
CASH FLOW FROM FINANCING ACTIVITIES      
Borrowings from revolving credit facility 730,000 1,165,000 334,000
Repayment of revolving credit facility (866,000) (1,034,000) (179,000)
Repayment of senior unsecured notes (250,000) (448,339)  
Borrowings from unsecured term loan 325,000 350,000  
Proceeds from mortgages and loans payable 513,989 455,190 10,752
Repayment of mortgages, loans payable and other obligations (156,760) (349,426) (43,133)
Acquisition of noncontrolling interests (2,021) (37,946)  
Issuance of redeemable noncontrolling interests, net 139,002    
Payment of contingent consideration     (1,167)
Payment of financing costs (9,230) (9,414) (2,998)
Contributions from (to) noncontrolling interests (19) 1,065 2,140
Payment of dividends and distributions (77,826) (60,041) (59,987)
Net cash provided by financing activities 346,135 32,089 60,607
Net (decrease) increase in cash and cash equivalents (3,431) (5,466) 7,528
Cash and cash equivalents, beginning of period 31,611 37,077 29,549
Cash and cash equivalents, end of period 28,180 31,611 37,077
Mack-Cali Realty LP [Member]      
CASH FLOWS FROM OPERATING ACTIVITIES      
Net income (loss) 33,718 130,294 (142,052)
Adjustments to reconcile net income to net cash provided by Operating activities:      
Depreciation and amortization, including related intangible assets 198,674 186,549 172,108
Amortization of directors deferred compensation stock units 482 372 397
Amortization of stock compensation 7,447 5,646 2,219
Amortization of deferred financing costs 4,612 4,582 3,790
Amortization of debt discount and mark-to-market (287) 1,686 3,385
Equity in (earnings) loss of unconsolidated joint ventures 6,081 (18,788) 3,172
Distributions of cumulative earnings from unconsolidated joint ventures 8,186 6,120 5,644
Gain on change of control of interests   (15,347)  
Realized (gains) losses and unrealized losses on disposition of rental property, net (2,364) (109,666) (53,261)
Gain on sale of investments in unconsolidated joint ventures (23,131) (5,670) (6,448)
Loss (gain) from extinguishment of debt 421 (12,420)  
Impairments     197,919
Changes in operating assets and liabilities:      
Increase in unbilled rents receivable, net (11,286) (12,775) (1,760)
Increase in deferred charges, goodwill and other assets (19,711) (33,878) (22,854)
Decrease (increase) in accounts receivable, net 2,831 596 (2,178)
Increase (decrease) in accounts payable, accrued expenses and other liabilities (9,012) (14,535) 6,960
Decrease in rents received in advance and security deposits (1,817) (3,297) (2,408)
Increase (decrease) in accrued interest payable 1,296 (9,362) 4,822
Net cash provided by operating activities 196,140 100,107 169,455
CASH FLOWS FROM INVESTING ACTIVITIES      
Rental property acquisitions and related intangibles (619,350) (407,869) (70,455)
Rental property additions and improvements (90,068) (121,582) (94,073)
Development of rental property and other related costs (267,845) (206,955) (81,073)
Proceeds from the sales of rental property 311,923 607,457 81,049
Proceeds from the sale of investments in unconsolidated joint ventures 110,269 6,420 6,448
Investments in notes receivable (47,049)    
Repayment of notes receivable 74,945 500 8,250
Investment in unconsolidated joint ventures (36,060) (35,930) (78,027)
Distributions in excess of cumulative earnings from unconsolidated joint ventures 5,877 22,231 6,445
Proceeds from investment receivable 3,625    
Decrease (increase) in restricted cash 8,027 (1,934) (1,098)
Net cash provided by investing activities (545,706) (137,662) (222,534)
CASH FLOW FROM FINANCING ACTIVITIES      
Borrowings from revolving credit facility 730,000 1,165,000 334,000
Repayment of revolving credit facility (866,000) (1,034,000) (179,000)
Repayment of senior unsecured notes (250,000) (448,339)  
Borrowings from unsecured term loan 325,000 350,000  
Proceeds from mortgages and loans payable 513,989 455,190 10,752
Repayment of mortgages, loans payable and other obligations (156,760) (349,426) (43,133)
Acquisition of noncontrolling interests (2,021) (37,946)
Issuance of redeemable noncontrolling interests, net 139,002    
Payment of contingent consideration     (1,167)
Payment of financing costs (9,230) (9,414) (2,998)
Contributions from (to) noncontrolling interests (19) 1,065 2,140
Payment of dividends and distributions (77,826) (60,041) (59,987)
Net cash provided by financing activities 346,135 32,089 60,607
Net (decrease) increase in cash and cash equivalents (3,431) (5,466) 7,528
Cash and cash equivalents, beginning of period 31,611 37,077 29,549
Cash and cash equivalents, end of period $ 28,180 $ 31,611 $ 37,077
[1] Amounts are net of amortization of basis differences of $792, $436 and $336 for the years ended December 31, 2017, 2016 and 2015, respectively.